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Objective: To detect the prevalence of mosaic loss of chromosome Y in adult men in ten study areas in China, describe the epidemiological distribution of mosaic loss of chromosome Y (mLOY) carriers and assess its prospective association with lung cancer. Methods: Based on the data from baseline survey, genetic analysis and follow-up (as of December 31, 2018) from China Kadoorie Biobank, we used Mosaic Chromosomal Alterations pipeline to detect mLOY carriers in 10 areas in China and described the epidemiological characteristics of mLOY carriers in adult men, including age, area distribution, lifestyle and disease history. We used multivariate logistic regression model to identify the potential relevant factor of mLOY. Cox proportional hazard regression model was fitted to assess the prospective association of mLOY with lung cancer. Stratification analysis were conducted to evaluate the potential modification effects of smoking and age. We also conducted mediation analysis to assess the mediating effect of mLOY in the association between smoking and lung cancer. Results: A total of 42 859 adult men were included in our analysis, in whom 2 458 mLOY carriers were detected (5.7%). The detection rate increased with age ( P <0.05). The detection rate was higher in urban area (7.3%±0.2%) than that in rural area (4.7%±0.1%). The results of logistic regression analysis indicated that smoking might be a risk factor for the detection of mLOY ( OR =1.49, 95% CI :1.36-1.64). After follow-up for average 11.1 years, 1 041 lung cancer cases were observed. The prospective analysis showed that mLOY carriers had an increased risk for lung cancer by 24% compared with non-mLOY carriers ( HR =1.24, 95% CI :1.01-1.52) and expanded mLOY carriers (mLOY cell proportion ≥10%) had an increased risk for lung cancer by 50% ( HR =1.50, 95% CI :1.13-2.00). Stratification analysis showed no modification effects of smoking and age in the association between mLOY and lung cancer (interaction P >0.05). Mediation analysis showed that mLOY could be a mediating factor in the association between smoking and lung cancer, the estimated effect was 0.09 (0.01-0.17). Conclusions: There were significant differences in the detection rate of mLOY in adult men with different social-economic characteristics and lifestyles in ten areas in China. Besides, mLOY carriers, especially expanded mLOY carriers, had increased risk for lung cancer and mLOY might be a mediating factor in the association between smoking and lung cancer.

Mosaic chromosomal alteration (mCA) is referred to as large-scale somatic mutations on chromosomes, which results in diverse karyotypes in body. The mCA is regarded as one of the phenotypes of aging. Studies have revealed its associations with many chronic diseases such as hematopoietic cancers and cardiovascular diseases, but its genetic basis (e.g. genetic susceptibility variants) is still under-investigated. This paper reviews GWAS studies for mCA on autosomal chromosomes and sex chromosomes [mosaic loss of the Y chromosome (mLOY) and mosaic loss of the X chromosome (mLOX)] based on large population, respectively. Most of the genetic susceptibility loci found in studies for autosomal mCA were associated with copy-neutral loss of heterozygosity. The study of sex chromosome mCA focused on mosaic loss mutations. The number of genetic susceptibility loci for mLOY was high (up to 156), but it was relatively less for mLOX.

Objective: To carry out prenatal diagnosis and genetic analysis for a fetus with disorders of sex development (DSDs)., Methods: A fetus with DSDs who was identified at the Shenzhen People's Hospital in September 2021 was selected as the study subject. Combined molecular genetic techniques including quantitative fluorescence PCR (QF-PCR), multiplex ligation-dependent probe amplification (MLPA), chromosomal microarray analysis (CMA), quantitative real-time PCR (qPCR), as well as cytogenetic techniques such as karyotyping analysis and fluorescence in situ hybridization (FISH) were applied. Ultrasonography was used to observe the phenotype of sex development., Results: Molecular genetic testing suggested that the fetus had mosaicism of Yq11.222qter deletion and X monosomy. Combined with the result of cytogenetic testing, its karyotype was determined as mos 45,X[34]/46,X,del(Y)(q11.222)[61]/47,X,del(Y)(q11.222),del(Y)(q11.222)[5]. Ultrasound examination suggested hypospadia, which was confirmed after elective abortion. Combined the results of genetic testing and phenotypic analysis, the fetus was ultimately diagnosed with DSDs., Conclusion: This study has applied a variety of genetic techniques and ultrasonography to diagnose a fetus with DSDs with a complex karyotype.

Objective: To investigate the clinical phenotype and genetic characteristics of disorders of sex development (DSD) caused by Y chromosome copy number variant (CNV). Methods: A retrospective analysis was performed on 3 patients diagnosed with DSD caused by Y chromosome CNV admitted to the First Affiliated Hospital of Zhengzhou University from January, 2018 to September, 2022. Clinical data were collected. Clinical study and genetic test were performed by karyotyping, whole exome sequencing (WES), low coverage whole genome copy number variant sequencing (CNV-seq), fluorescence in situ hybridization (FISH) and gonadal biopsy. Results: The 3 children, aged 12, 9, 9 years, the social gender were all female, presented with short stature, gonadal dysplasia and normal female external genital. No other phenotypic abnormality was found except for case 1 with scoliosis. The karyotype of all cases were identified as 46, XY. No pathogenic vraiants were found by WES. CNV-seq determined that case 1 was 47, XYY,+Y(2.12) and case 2 was 46, XY,+Y(1.6). FISH concluded that the long arm of Y chromosome was broken and recombined near Yq11.2, and then produced a pseudodicentric chromosome idic(Y). The karyotype was reinterpreted as mos 47, X, idic(Y)(q11.23)×2(10)/46, X, idic(Y)(q11.23)(50) in case 1. The karyotype was redefined as 45, XO(6)/46, X, idic(Y)(q11.22)(23)/46, X, del(Y)(q11.22)(1) in case 2. 46, XY, -Y(mos) was found by CNV-seq in case 3, and the karyotype of 45, XO/46, XY was speculated. Conclusions: The clinical manifestations of children with DSD caused by Y chromosome CNV are short stature and gonadal dysgenesis. If there is an increase of Y chromosome CNV detected by CNV-seq, FISH is recommended to classify the structural variation of Y chromosome.

Objective: To compare the six-sequence-tagged site (STS) with the eight-STS scheme in the detection of Y chromosome microdeletions., Methods: Using real-time quantitative PCR, we compared the results of the six-STS (sY84, sY86, sY127, sY134, sY254, sY255) scheme with those of the eight-STS (sY84, sY86, sY127, sY134, sY254, sY255, sY145, sY152) scheme in detecting Y chromosome microdeletions., Results: No statistically significant difference was found in the detection rate of the deletion of the azoospermia factor (AZF) regions between the six-STS and eight-STS methods (9.34% ［575/6177］ vs 8.85% ［542/6122］, P > 0.05)., Conclusion: Though the eight-STS scheme increased the detection of AZFd, its detection rate of the AZF region deletion was not significantly different from that of the six-STS method. From the perspectives of experimental operation, economic cost and clinical strategy guidance, the six-STS is better than the eight-STS scheme for the detection of Y chromosome microdeletions.

Objective: To analyze the clinical treatment results of male infertility caused by Y chromosome azoospermia factor c region(AZFc) deletion after synchronous micro-dissection testicular sperm extraction (micro-TESE) and intracytoplasmic sperm injection (ICSI) and to guide the treatment of infer- tile patients caused by AZFc deletion., Methods: The clinical data of infertile patients with AZFc deletion who underwent synchronous micro-TESE in Peking University Third Hospitalfrom January 2015 to December 2019 were retrospectively analyzed. The clinical outcomes of ICSI in the patients who successfully obtained sperm were followed up and we compared the outcomes between the first and second synchronous procedures, including fertilization rate, high-quality embryo rate, clinical pregnancy rate, abortion rate and live birth rate., Results: A total of 195 male infertile patients with AZFc deletion underwent micro-TESE. Fourteen patients were cryptozoospermia and their sperms were successfully obtained in all of them during the operation, and the sperm retrieval rate (SRR) was 100%(14/14). The remaining 181 cases were non obstructive azoospermia, and 122 cases were successfully found the sperm, the SRR was 67.4%(122/181). The remaining 59 patients with NOA could not found mature sperm during micro-TESE, accounting for 32.6% (59/181). We followed up the clinical treatment outcomes of the patients with successful sperm retrieved by synchronous micro-TESE and 99 patients were enrolled in the study. A total of 118 micro-TESE procedures and 120 ICSI cycles were carried out. Finally 38 couples successfully gave birth to 22 male and 22 female healthy infants, with a cumulative live birth rate of 38.4% (38/99). In the fresh-sperm ICSI cycle of the first and second synchronous operation procedures, the high-quality embryo rate, clinical pregnancy rate of the fresh embryo transfer cycle and live birth rate of the oocyte retrieve cycle were 47.7% vs . 50.4%, 40.5% vs . 50.0%, and 28.3% vs . 41.2%, respectively. The second operation group was slightly higher than that of the first synchronous operation group, but there was no significant difference between the groups., Conclusion: Male infertility patients caused by AZFc deletion have a high probability of successfully obtaining sperm in testis through micro-TESE for ICSI and give birth to their own offspring with their own biological characteristics. For patients who failed in the first synchronous procedure, they still have the opportunity to successfully conceive offspring through reoperation and ICSI.

Objectives: To construct a Felis catus STR loci multiplex amplification system and to evaluate its application value by testing the technical performance., Methods: The published Felis catus STR loci data were reviewed and analyzed to select the STR loci and sex identification loci that could be used for Felis catus individual identification and genetic identification. The fluorescent labeling primers were designed to construct the multiplex amplification system. The system was validated for sensitivity, accuracy, balance, stability, species specificity, tissue identity and mixture analysis, and investigated the genetic polymorphisms in 145 unrelated Felis catus samples., Results: Sixteen Felis catus autosomal STR loci and one sex determining region of Y (SRY) were successfully selected, and constructed a multiplex amplification system containing the above loci. The complete profile of all alleles could still be obtained when the amount of DNA template was as low as 0.25 ng. There was no specific amplification peak in other common animal samples. Population genetic surveys showed that total discrimination power (TDP) of the 16 STR loci was 1-3.57×10 -20 , the cumulative probability of exclusion (CPE) was 1-6.35×10 -5 and the cumulative probability of matching was 3.61×10 -20 ., Conclusions: The Felis catus STR multiplex amplification system constructed in this study is highly sensitive, species-specific, and accurate in typing results, which can provide an effective solution for Felis catus species identification, individual identification and kinship identification in the field of forensic science.

Objective: To study the semen parameters of the patients with Y chromosome microdeletions and their impacts on the spermatogenesis of the patients., Methods: We selected 151 male infertility patients with Y chromosome microdeletions from those diagnosed and treated in our hospital and retrospectively analyzed the influence of their semen parameters on the spermatogenic function., Results: Of the 151 cases of Y chromosome microdeletions, AZFc was involved in 102 (66.89%), AZFb in 6 (3.97%), AZFa in 5 (3.31%), AZFa+c in 1 (0.66%), AZFb+c in 6 (3.97%), AZFc+d in 1 (0.66%), AZFb+c+d in 13 (8.61%), AZFa+b+c+d in 12 (7.95%), sY127 in 3 (1.99%), sY134 in 1 (0.66%) and sY86 in 1 (0.66%). Among the total number of the infertility patients, 48 (31.78%) were diagnosed with azoospermia, 74 (49%) with cryptozoospermia, 28 (18.54) with oligoasthenozoospermia and 1 (0.66%) with asthenoteratozoospermia., Conclusions: Y chromosome microdeletions may lead to decreased sperm quality, and different types of deletion have different impacts on the spermatogenic function of the patients.

Objective: To carry out genetic testing for a XXY fetus suggested by non-invasive prenatal testing (NIPT)., Methods: G-banding karyotyping, fluorescence in situ hybridization (FISH) and chromosomal microarray analysis (CMA) were performed on amniocytes from the fetus. The genitalia of the fetus was also examined by Doppler ultrasonography. The result was verified with peripheral blood samples from its parents and a brother., Results: The fetus was found to have a 46,XX karyotype. CMA showed presence of sequences from Yp11.2 (2.635 Mb) and Yp11.31p11.2 (3.706 Mb). FISH assay suggested that the SRY fragment on Yp has translocated to Xpter. No karyotypic or pathogenic CNVs was detected in its parents and brother. The fetus was ultimately diagnosed with 46,XX (SRY positive) male syndrome., Conclusion: The combination of G-banding karyotyping, FISH, and CMA is of great significance for attaining accurate prenatal diagnosis for this fetus.

Objective: To carry out prenatal diagnosis for a fetus with increased nuchal translucency (NT) and another fetus with non-invasive prenatal testing (NIPT) suggested reduced sex chromosomes by cytogenetic and molecular techniques., Methods: Chromosomal karyotyping, single nucleotide polymorphism array (SNP-array) and fluorescence in situ hybridization (FISH) were applied for the diagnoses. Peripheral blood samples were also taken from their parents for chromosomal karyotyping and SNP-array analysis., Results: Both fetuses showed a 46,X,+mar/45,X karyotype. SNP-array has detected a 22.0 Mb duplication at Yp11.31q11.223 and a 3.9 Mb microdeletion at Yq11.223q11.23 in fetus 1, and a 16.9 Mb duplication at Yp11.31q11.221 and a 8.1 Mb deletion at Yq11.222q11.23 in fetus 2. The results were confirmed by FISH. The parents of both fetuses were normal by chromosomal karyotyping and SNP-array., Conclusion: Combined use of various techniques can enable accurate prenatal diagnosis and genetic counseling.

Objective: To perform prenatal diagosis for two fetuses carrying partial deletion of Y chromosome., Methods: Routine G- and C-banding were carried out to analyze the chromosomal karyotypes of the fetuses and their fathers. Fetal DNA was also subjected to low-coverage massively parallel copy number variation sequencing (CNV-seq), fluorescence in situ hybridization (FISH), SRY gene and AZF factor testing., Results: Both fetuses showed a 46, XN, del(Y) (q11.2) karyotype at 320-400 band level by the analysis of amniotic fluid chromosomes. FISH with Y chromosome centromere probe indicated that in both cases the number of Y chromosome was normal. Both fathers had an apparently normal karyotype at 320-400 band level. For fetus 1, CNV-seq test revealed a 12.88 Mb deletion at Yq11.221-q12, which encompassed the whole of AZFb+AZFc regions and may lead to male infertility, sperm deficiency and/or severe oligospermia. In fetus 2, CNV-seq also detected a 14.84 Mb deletion at Yq11.21-q12, which encompassed the whole of the AZF region and may lead to severe spermatogenesis disorder resulting in severe oligoasthenospermia and azoospermia. In both cases, testing of SRY gene was positive. No point mutation of the SRY gene was identified. Analysis of amniotic fluid DNA confirmed partial or total absence of AZF in the two fetuses, respectively., Conclusion: Combined use of various technologies can enable accurate detection of structural abnormalities of the Y chromosome and facilitate genetic counseling. CNV-seq can help with rapid screening of Y chromosome microdeletions and may be used as a complementary test for chromosomal karyotyping.

Abstract: Objective To explore the genetic polymorphism of Y chromosome D-M174 haplogroup and sub-haplogroups in East Asia. Methods The samples of 1 426 unrelated male individuals from East Asia were collected, and then 7 Y chromosome haplogroup D-M174 and the Y-SNP of its sub-haplogroups were detected with mini-sequencing. The 22 Y-STR genotypes were detected with DNA Typer™ Y26 kit. The haplogroup was analyzed using direct counting method, heatmap, phylogenetic cluster and network graph cluster, and then distribution of genetic polymorphism and the clustering relation between populations and samples of Y chromosome D haplogroup were discussed. Results Haplogroup D-M174 were distributed mostly among Tibetans （40.96%）and Japanese （35.71%）, while less or none were distributed among the surrounding areas of Tibet and other areas. Conclusion The geographical distribution of Y chromosome D-M174 haplogroup in East Asian populations has significant characteristics., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Abstract: Objective To explore the distribution of genetic structure of Y-SNP and Y-STR genetic markers in different ethnic groups and its application in forensic science. Methods SNaPshot minisequencing was used to detect the polymorphisms of 12 Y-SNP loci in 439 males from 6 ethnic groups, including Guangxi Han, Guangxi Jing, Guangxi Miao, Guangxi Yao, Guangxi Zhuang and Guangxi Dong. DNATyperTM Y26 kit was used to multiplex-amplify 26 Y-STR loci. The PCR products were analyzed by 3130xl genetic analyzer. The network analysis of Y-STR haplotype under the same Y-SNP haplogroup was analyzed by Network 5.0 software. Results Six haplogroups defined by 12 Y-SNP loci were detected in 6 ethnic groups, and 362 haplotypes were detected in 26 Y-STR loci. The haplotype diversity was 0.996 6. In the C haplogroup, the samples from Guangxi Yao, Guangxi Zhuang and Guangxi Dong were clustered on different branches; in the O1 haplogroup, those from Guangxi Zhuang, Guangxi Miao and Guangxi Jing were relatively independent and clustered separately; in the O2 haplogroup, some samples from Guangxi Miao and Guangxi Yao were gathered in a cluster. Conclusion Based on the Y-STR network analysis of samples with identical haplogroup of Y-SNP, some ethnic groups can be preliminarily distinguished, which could be used to infer male suspects' ethnic group through detecting their genetic markers left in the crime scene., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Abstract: Objective To investigate the application of the comprehensive use of multiple genetic markers in full and half sibling relationship testing through the identification of a case of suspected sibling relationship. Methods Genomic DNA were extracted from bloodstain samples from 4 subjects （ZHANG-1, ZHANG-2, male; ZHANG-3, ZHANG-4, female）. Autosomal STR loci, X-STR, Y-STR loci and polymorphisms of mtDNA HV-Ⅰ and Ⅱwere genotyped by EX20 STR kit, X19 kit, Data Y24 STR kit, and Sanger sequencing, respectively. Results According to autosomal STR based IBS scoring results, full sibling relationships were indicated among ZHANG-2, ZHANG-3 and ZHANG-4, but those were not indicated between ZHANG-1 and ZHANG-2 or ZHANG-3 or ZHANG-4. According to autosomal STR based FSI and HSI, with ITO method and discriminant function method, full sibling relationships among ZHANG-2, ZHANG-3 and ZHANG-4 were indicated, and half sibling relationships between ZHANG-1 and ZHANG-2 or ZHANG-3 or ZHANG-4 were also indicated. X-STR and mtDNA sequencing results showed that all the 4 samples came from a same maternal line, and Y-STR results showed that ZHANG-1 and ZHANG-2 did not come from a same paternal line, which supported the half sibling relationship between ZHANG-1 and ZHANG-2 or ZHANG-3 or ZHANG-4, verified by parental genotype reconstruction based on autosomal STR genotyping. Conclusion For the identification of sibling relationships, it is effective to have reliable results with the mutual verification and support of multiple genetic markers （autosomal STR, sex chromosomal STR and mtDNA sequence） and calculations （IBS, ITO, discriminant function method and family reconstruction）., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Objectives: To analyze the polymorphism of 71 SNP loci on Y chromosome in Han population of Northwest China, to assess its forensic application value, and to screen out Y-SNP loci for forensic examination of Han population in East, South, and Northwest China based on the integration of previous research results., Methods: Multiplex polymerase chain reaction （PCR） and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） were performed on 71 Y-SNP loci of 202 unrelated Han male individuals in Northwest China. Gene diversity （GD） and haplotype diversity （HD） values were calculated, and then Y-SNP loci of Han population in East, South, and Northwest China were screened with the combination of data from previous research., Results: Among the detected 71 loci, 67 loci were polymorphic in the Northwest Han male population, with GD values 0.010 0-0.502 2. There were 22 and 25 loci with a moderate （0.2≤GD<0.3） and high （GD≥0.3） amount of genetic information, respectively. There were 26 loci for the Han communities in Northwest, South, and East China., Conclusions: Y-SNP loci are potential in paternity testing and individual identification, as well as the judgement of population distribution and migration., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Objective: To explore the incidience of chromosome abnormality of the patients with oligozoospermia or azoospermia and male infertility, to discuss the relationship between the quantitative and structural abnormality of chromosome and to lay the foundation for the clinical diagnosis and consultation., Methods: A retrospective analysis was conducted from January 1, 2015 to May 1, 2016, in the Center for Reproduction Medicine, the Second Hospital of Jilin University, with male reproductive abnormalities history excluded. In the study, 1 324 cases were included with 448 cases of azoospermia and 876 cases of oligozoospermia. All the patients through ultrasound examination, color Doppler ultrasonography, the seminal plasma Zn determination, their hormone level determination, chromosome karyotype (the perinatal blood samples were obtained from the 1 324 patients with oligozoospermia or azoospermia for lymphocyte culture, then chromosomal specimens were prepared, G-banding analyses combined with clinical data were used to statistically analyze the incidence of chromosomal abnormality), Y chromosome azoospermia factor [PCR technique was used to detect SY157 locus, SY254 locus, and SY255 locus in male Y chromosome azoospermia factor (AZF) gene of the patients with oligozoospermia or azoospermia]. The relationship between chromosome abnormalities and oligozoospermia or azoospermia were analyzed., Results: Among the 876 cases of oligospermia patients, 78 cases were chromosome number abnormality and chromosomal structural abnormality, the abnormal number of sex chromosomes in 22 cases, and sex chromosomes and chromosome structural abnormalities in 56 cases; in the 448 cases of azoospermia patients, 91 cases were chromosomal structural abnormality and chromosome number abnormality, of them, 78 cases were of abnormal number of sex chromosomes, and 13 cases were of abnormal structure. In addition, 137 cases were of chromosome polymorphism in all the 1 324 patients, The incidence of Y chromosome abnormality in azoospermatism was higher than that of the 43 patients with Y chromosome AZF microdeletion. In addition, the asthenospermia and recurrent spontaneous abortion were closely related to Y chromosome abnormality and the chromosome translocations and inversions., Conclusion: Oligozoospermia and azoospermia patients with abnormal chromosome karyotype have high incidence rate, and chromosome karyotype analyses were carried out on it, which is conducive to clinical diagnosis for the patients with abnormal chromosome karyotype. There is a close relationship between male infertility and abnormal karyotype. It is conducive to clinical diagnosis for the patients with infertility through chromosome karyotye analysis, which also provides evidence for genetic counseling.

One case of family chromosomal karyotype with complex chromosomal translocation and male infertility was reported. This case is a male, 30 years old, Han nationality, who did not receive contraception for 3 years after marriage. The phenotype and intelligence of the patients were normal, and there were no abnormalities in the external genitalia. No abnormalities were found in the prostate and spermatic vein. There was no history of parotitis or testicular trauma, no history of smoking, drinking history, denial of harmful substances and history of radioactive contact. There were no similar patients in the family, and the secondary sex was normal. The routine semen examination suggested that the active sperm was seldom seen. There were no obvious abnormalities in the serum endocrine examination of the patient. Cytogenetic examination: the patient's karyotype 46XY, t (10; 18; 21) (q22; p11.2; q11.2). There was no deletion in locus sY84, sY86, sY127, sY134, sY143, sY254 and sY255. His wife's examination showed no obvious abnormality, and her karyotype was normal. The parents of the patients were not close relatives. Their father's chromosome karyotype analysis was 46, XY, and Y chromosome microdeletion was normal. The chromosome karyotype of the parent was 46XX, t (10; 18; 21), and the parents of the patient also had a daughter, whose phenotype and intellectual development were normal, chromosome karyotype 46XX, t (10; 18; 21). In this case, the patient's balance translocation should be inherited by the mother. Because of the normal phenotype of the patient, there was no loss of genetic material, but the abnormal chromosomes might be passed to the offspring, and the proportion of the unbalanced gametes was very high. Through systematic review and review of the cases, it was concluded that the balanced translocation carriers only changed the relative position of the translocation segments on the chromosomes, retained the total number of the original genes, only changed the relative position of the genes on the chromosomes, and had no serious effect on the role of the gene and the development of the individual. The phenotype was normal. The patients were given symptomatic treatment to improve semen quality. It is recommended that pre-implantation genetic screening/diagnosis(PGS/PGD) be performed if necessary. It is to guide married men and women to choose the appropriate childbearing age, avoid unhealthy environmental contacts, and strengthen genetic screening before and after pregnancy, so as to achieve the goal of eugenics.

Objectives: To investigate the genetic polymorphisms of 27 Y-STR in Dongxiang population of Gansu province, and to explore the population genetic relationship and the value of forensic application., Methods: The genotyping of 27 Y-STR loci in 526 unrelated male individuals in Dongxiang population of Gansu province were detected by STRtyper-27Y kit. The allele frequencies and haplotype diversity were also calculated. Combining with other genetics data of 14 loci in same populations, which have been published at home and abroad, the genetic distance and clustering relationship in Dongxiang population of Gansu province were calculated., Results: Totally 55 haplotypes were found in the DYS385a/b biallelic loci, 39 haplotypes in DYF387S1 loci, and 4-16 alleles in the rest 23 single copy STR loci. The GD value was from 0.453 9 （ DYS391 ） to 0.957 5 （ DYS385a/b ）. Totally 471 haplotypes were observed in 27 Y-STR loci in 526 individuals, and the value of haplotypes diversity was 0.999 5. The genetic distance between Dongxiang and Tibetan populations of Gansu province was the closest （0.068 2）, while it was the longest between Dongxiang population in Gansu province and Han population in Henan province （0.084 7）. The result of dimensional analysis established upon the genetic distance was basically matched with that of the cluster analysis., Conclusions: The 27 Y-STR loci show a high genetic polymorphism in Dongxiang population of Gansu province, which has significance for the Y-STR database establishment, population genetics study and forensic practice., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Objectives: To select a Y-STR marker system with strong haplotype identification ability, appropriate mutation rate and high compatibility and to assess its forensic application., Methods: The 24 Y-STR loci were tested by self-built fluorescent multiplex system, and the forensic assessment was conducted by 139 pairs of father-son samples collected in Jinan, Shandong province., Results: Totally 176 alleles were identified among the 24 Y-STR loci in the sample of 139 unrelated individuals labeled with father, and the gene diversity （GD） distributed between 0.083 7 （ DYS645 ）-0.966 9 （ DYS385a/b ）. According to the 24 Y-STR loci, 139 different haplotypes were detected from 139 unrelated male individuals labeled with father in Han population of Shandong province and with no shared haplotype observed. The overall haplotype diversity （HD） was 1 and the discrimination capacity （DC） was 1. A total of 5 one-step mutations events were observed among the 24 Y-STR loci in 139 pairs of father-son. The average mutation rate was 0.001 5 [95% CI （0.000 5, 0.003 5）]., Conclusions: The system of 24 Y-STR loci shows a strong individual recognition ability and low mutation rate in the population in Jinan, Shandong province, and it has good application value in forensic science., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Objective: To investigate the association of the abnormal length of human Y chromosome with semen quality and the outcome of assisted reproductive technology (ART)., Methods: Based on the karyotype, we assigned the patients undergoing ART to a normal control, a long Y chromosome (Y>18), and a short Y chromosome group (Y<22). We compared the semen parameters and numbers of embryos and high-quality embryos among the three groups of patients and performed statistical analysis of the obtained data using Chi-square distribution and t-test., Results: Compared with the control, the Y>18 group showed a significantly lower incidence rate of asthenozoospermia (31.03% vs 8.33%, P <0.05) and a larger number of high-quality embryos (5.46 ± 4.54 vs 7.40 ± 5.49, P<0.05). Both the incidence rate of azoospermia and number of total embryos were remarkably lower in the control than in the Y<22 group (1.87% vs 16.47%, P <0.05; 8.60 ± 7.03 vs 10.00 ± 6.58, P<0.05). No statistically significant differences were found in the pregnancy rate between the Y>18 and Y<22 groups (P>0.05)., Conclusions: Short Y chromosome may affect spermatogenesis, but the length of Y chromosome does not negatively influence the outcome of ART.

Objective: To discuss the treatment options for patients with azoospermia factor (AZF) c microdeletion on Y chromosome., Methods: One hundred and eighty three patients, who were diagnosed as AZFc microdeletion on Y chromosome in Peking University Third Hospital, were recruited in our study. In order to get better treatment option for this kind of patients, we retrospectively analyzed their clinic data including the treatment process and pregnancy outcome and found out the characteristics of their semen., Results: Among the 183 patients, sperms can be found in ejaculated semen in 105 patients (57.4%, 105/183). One hundred and three patients (98.1%, 103/105) were diagnosed as severe or extremely severe oligospermia. Regular medication was given to 98 patients, 6 patients (6.1%, 6/98) of which got natural pregnancy. The other 99 patients who have sperms in their semen received intracytoplasmic sperm injection (ICSI), 68 patients (68.7%, 68/99) of which got pregnancy. Seventy eight patients were diagnosed as azoospermia among all the 183 patients. Forty nine patients received testicular sperm aspiration (TESA), and 21 patients choose to receive micro-TESE directly. Among the 49 patients with TESA, sperms were retrieved in 17 patients (34.7%, 17/49), and sperms were not retrieved in 32 patients (65.3%, 32/49), of which 12 patients (37.5%, 12/32) gave up treatment and 20 patients (62.5%, 20/32) choose micro-TESE. Among the 41 patients who choose to receive micro-TESE, operation has been done on 19 patients, of which 11 patients (57.9%, 11/19) got sperms. Among the 11 patients, TESA has been done on 6 patients before micro-TESE, of which 4 patients (66.6%, 4/6) got sperms. ICSI has already been done on 7 azoospermia AZFc microdeletion patients who underwent micro-TESE, of which 4 patients (57.1%, 4/7) get pregnancy., Conclusion: AZFc microdeletion patients who had sperms were always diagnosed as severe or extremely severe oligospermia. ICSI was their first choice instead of drug therapy. For AZFc microdeletion patients who were diagnosed as azoospermia, TESA was one of their choices, however, the success rate is not high. Micro-TESE is still possible to get sperms even after the failure of TESA. Therefore, we may choose micro-TESE instead of TESA in some azoospermia patients in order to reduce surgical trauma on patients.

Objective: To establish an accurate, fast and simple screening method for AZF microdeletions using capillary technology and use it for clinical testing., Methods: For each pair of primers, the 5' end of either forward or reverse primer was labeled with a FAM, JOE or TAMRA fluorescence dyes to establish multiplex quantitative fluorescence PCR systems for the establishment of a screening method of Y chromosome AZF microdeletions by capillary technology. The detection of Y chromosome AZF microdeletion was carried out on 725 cases of non-obstructive azoospermia, oligospermia or asthenospermia., Results: A screening method for Y chromosome AZF microdeletions using capillary technology was established. Thirty eight cases of AZF microdeletions were found among 725 cases of non-obstructive azoospermia, oligospermia or asthenospermia, which gave a deletion rate of 5.24%. Y chromosomal microdeletions were found in 8.62% of the azoospermia group, 6.75% of the oligozoospermic group, and 2.23% of the asthenospermia group., Conclusion: An accurate, fast and simple screening method of Y chromosome AZF microdeletions by capillary technology has been established, which may have an important clinical value.

Objective: To investigate the phenotype-genotype association of isodicentromere Y chromosome by analysis of two female patients carrying the chromosome with sexual development disorders., Methods: The karyotypes of the two patients were determined by application of conventional G banding of peripheral blood samples and fluorescence in situ hybridization (FISH). PCR was applied to detect the presence of SRY gene., Results: Conventional karyotype analysis showed case 1 to be a mosaic: mos.45,X[38]/46,X,+mar[151]/47,XY,+mar[5]/47,X,+mar × 2[2]/46,XY[4], FISH showed that 12 different cell lines were presented in the karyotype of case 1 and partial cell lines with SRY gene, the marker is an isodicentromere Y chromosome [idic(Y)(p)]. No mutation was found in the SRY gene. The karyotype of case 2 was mos.45,X[25]/46,X,+mar[35]. FISH showed the marker to be an idic(Y)(p) without the SRY gene., Conclusion: The karyotype of patients carrying idic(Y)(p) seems unstable, and female patients have the characteristics of short stature and secondary sexual hypoplasia. Karyotype analysis combined with FISH analysis can accurately determine the breakpoint of idic(Y) and identify the types of complex mosaic, which may facilitate genetic counseling and prognosis.

Objective: To establish a 29 Y-STR loci multiplex PCR system for investigating the genetic polymorphisms and to assess its application value in forensic science., Methods: A multiplex PCR system was established using a five color fluorescence labeling 29 Y-STR loci (DYS456, DYS389 I , DYS437, DYS447, DYS389 11, DYS438, DYS522, DYS460, DYS458, DYS622, DYS390, DYS392, DYS448, DYS449, DYS391, Y-GA TA-H4, DYS388, DYS19, DYS385a/b, DYS527a/b, DYS393, DYS459a/b, DYS635, DYS439, DYS570 and DYS627) for multiple amplification and capillary electrophoresis. And its applicability was validated with genetic polymorphism data of 29 Y-STR of unrelated 2,000 male samples in Shandong Han population., Results: A total of 1,981 different haplotypes of 2,000 individuals showed genotype diver- sity between 0.370 0 and 0.965 4. The system provided stable and accurate typing with high sensitivity of 0.05 ng. It satisfied the needs of variety of routine biological samples., Conclusion: The 29 Y-STR loci multiplex PCR system could be applied for actual cases and establishment of Y-STR database. In addition, it has great significance in forensic science practices and related research.

Objective: To evaluate the correlation between chromosomal polymorphisms and male sperm quality in Jilin Province., Methods: A total of 2 584 male patients with infertility in Center for Reproductive Medicine, First Bethune Hospital of Jilin University from 2008 to 2013 were enrolled, which semen analysis, chromosomal analysis, Y chromosome microdeletion analysis and serum hormone levels analysis were performed. A total of 602 healthy individuals, 50 fertile individuals with normal kayrotypes, 50 azoospermia patients with normal kayrotypes and 50 oligospermia patients with normal kayrotypes were selected as control groups., Results: There was no significant difference in the frequency of chromosome polymorphisms between infertile patients and normal control individuals (3.91% (101/2 584) vs 3.16% (19/602), P > 0.05). And there was no significant difference in the frequency of autosomal polymorphisms between infertile patients and normal control individuals (all P > 0.05). The frequency of Yqh-variant was increased by the decrease of sperm count and it appeared a significantly high frequency in azoospermia patients compared with oligospermia patients and sperm count normal patients in the infertile group (57.14% (21/42) vs 24.32% (9/37), 0 (0/13), both P < 0.05). There was no significant difference in the testis volume and serum hormone levels between the infertile patients with chromosomal polymorphisms and patients in control groups with normal kayrotypes (all P > 0.05). The results of PCR amplication indicated that 32.14% (9/28) patients with Yqh ± had Y chromosome microdeletion., Conclusions: There is no significant correlation between autosomal polymorphisms and male infertility. But Yqh ± may be responsible for Y chromosome microdeletion and male infertility.

Objective: To test and estimate the forensic application of Goldeneye™ DNA ID 25A Kit., Methods: The kit was validated by a series of tests for accuracy, sensitivity, consistency, peak height balance, stability, and mixed samples through measured blood samples and other samples in routine casework., Results: The peak height balance of the different loci was ≥ 42%. The genotyping results of the positive control DNA was accurate. The complete STR genotyping result could be obtained from 0.125 ng positive control DNA., Conclusion: Goldeneye™ DNA ID 25A Kit is suitable for criminal cases and DNA database in forensic practice.

Objective: To investigate the location and characteristics of microdeletions of Y chromosome azoospermia factor (AZF) genes in infertile males with azoospermia and severe oligozoospermia in southern Sichuan., Methods: Multiplex PCR was used to detect 18 sequence tagged sites (STS) involved in Y chromosome AZF microdeletions among 224 infertile males (including 134 azoospermia cases and 90 severe oligozoospermia cases) and 70 healthy males., Results: Among the 224 infertile males, the overall frequency of microdeletions was 12.1% (27/224), and were 13.4% (18/134) in those with azoospermia and 10.0% (9/90) in those with severe oligozoospermia. The most frequent microdeletions have occurred in the AZFc region (51.9%). Compared with the 6 STS loci recommended by European Academy of Andrology and European Molecular Genetics Quality Network, 22.7% more deletions were detected based on the 18 STS loci selected from the AZF region., Conclusion: Identification of Y chromosome microdeletions has a significant implication on the diagnosis of male infertility. The most frequent microdeletions have occurred in the AZFc region in southern Sichuan. To use more sequence tagged sites for the screening can improve the reliability and detection rate of Y chromosome microdeletions.

Objective: To perform the validation and analysis of forensic parameters of Goldeneye DNA ID 26Y system., Methods: Based on the validation rules of Scientific Working Group on DNA Analysis Methods (SWGDAM), the kit was assessed from several parts, as test of PCR system, reproducibility, accuracy, and sensitivity, etc. And Y-STR loci of 517 unrelated healthy individuals from Eastern China were genotypes by this kit. The distribution and frequency of haplotype were calculated and forensic parameters of the kit were assessed., Results: The complete profiles can be obtained even when the PCR reaction volume with 6.25 microL. And correct profile was obtained with DNA down to 125 pg. No reproducible peaks were detected with the DNA of common animals and microorganism with the kit. For the male-male mixture testing, average 70% of the minor alleles were obtained when the ratios of 1:19 and 19:1. For the male-female mixture testing, results showed that the sensitivity of the kit was no compromised with the addition of female samples., Conclusion: The validation studies demonstrated that Goldeneye DNA ID 26Y system has good sensitivity and specificity, and suitable for mixture testing. The polymorphism of 26 Y-STR loci included in this kit are good for forensic application.

Objective: To assess the value of combined evaluation of serum follicle-stimulating hormone (FSH), inhibin B (INHB), chromosome karyotyping and AZF microdeletion of Y-chromosome (AZF-MD-Ych) in predicting the success of testicular sperm aspiration (TESA) in azoospermic patients., Methods: A total of 262 azoospermic patients were divided into two groups with normal (n=162) and abnormal (n=100) serum FSH levels. INHB levels, INHB/FSH ratio, chromosome karyotype patterns of the peripheral lymphocytes, and AZF-MD-Ych were compared between the two groups. Among the patients receiving TESA, the success rate of the procedure was compared between the two groups after excluding abnormalities in INHB, chromosome karyotype and AZF-MD-Ych., Results: Significant differences were found between the two groups in serum INHB level, INHB/FSH and chromosome karyotypes (P<0.05), but not in AZF-MD-Ych (P>0.05). After excluding the abnormalities in chromosome karyotypes, AZF-MD-Ych and INHB, sperms were obtained successfully by TESA from 61.82% (34/55) of patients with normal FSH but from none of those with abnormal FSH (P<0.01)., Conclusion: A combined evaluation of serum FSH, INHB, chromosome karyotypes and AZF-MD-Ych can effectively predict the success of TESA in azoospermic patients, and abnormalities in all the 4 indices suggest a very low success rate of sperm retrieval by TESA.

This study was aimed to investigate the clinical characteristics of acute myeloid leukemia (AML) with t (8;21) (q22;q22) and loss of Y chromosomes. Clinical data of 267 cases of AML were collected from January 2010 to June 2013. Among 267 AML, there were 13 cases with t (8;21) (q22;q22) and loss of Y chromosomes. The clinical data including clinical indicators, treatment protocols, curative effect and prognosis were analyzed retrospectively. The results showed that after normalized chemotherapy, there were 4 patients with complete remission at the first cycle of treatment, 4 patients with complete remission at the second cycle, 4 patients with complete remission at the third cycle, but one patient without complete remission after 4 cycles. There were 6 patients who did not relapse during consolidation and intensive therapy. Among these 6 patients, 4 cases accepted chemotherapy combined with transplantation, other 2 cases accepted chemotherapy. In the remainder 6 patients, 4 cases relapsed once, one cases relapsed twice, 1 cases relapsed for three times. Moreover, 2 cases who accepted the chemotherapy and auto-hematopoietic stem cell trans-plantation, were diagnosed as relapse, after accepted allo-hematopoietic stem cell transplantation, currently are in disease-free status. In follow-up period, the relapse-free survival (RFS) time was 4.67 ± 3.45 months in chemotherapy group, the RFS time is 34.17 ± 21.37 months in chemotherapy and transplantation group. The chemotherapy combined with transplantation extended the RFS time (P < 0.05). It is concluded that the NCCN guide indicates that AML with t (8;21) ( q22;q22) showed a good prognosis. but the clinical course of treatment confirmed that the prognosis of AML patients with t (8;21) (q22;q22) and loss Y chromosomes is poor, including uneasy remission and easy relapse, for improving the prognosis of these patients, the hematopoietic stem cell transplantation should be recommended.

Objective: To investigate the origin of a rare supernumerary chromosome in a patient with premature ovarian failure (POF), and to explore the relationship between this abnormal karyotype and pathogenesis of POF., Methods: GTG banding karyotyping, Q-banding and fluorescence in situ hybridization (FISH) were employed for the investigation., Results: The extra chromosome was identified as i(Y)(q10) by FISH with a panel of sex chromosome probes. The patient's karyotype was described as: 47,XX,+ ish mar i(Y)(q10) (DXZ1-, SRY-, DYZ3+, DYZ1++, wcpY+)., Conclusion: Co-occurrence of the supernumerary i(Y)(q10) with a female kryotype is extremely rare. This supernumerary chromosome may cause failure of X chromosomes synapsis during pachytene of meiosis I, which may trigger apoptosis of many oocytes and result in POF of the patient. Q-banding, FISH and multiple probes have been critical for accurate diagnosis of the unknown chromosome.

Objective: To explore genetic etiologies of a patient with severe oligozoospermia and asthenozoospermia., Methods: G-banded karyotyping and fluorescence in situ hybridization (FISH) were used to characterize the origin and structure of the abnormal chromosome discovered in this patient. Multiplex polymerase chain reaction (PCR) was used to detect microdeletion of azoospermia factor (AZF)., Results: G-banding revealed a karyotype of 45,X,der(15) (?::p11.2→ qter)dn for the patient. Dual-color FISH confirmed that SRY gene was present in a segment attached to the short arm of chromosome 15. Sex chromosome mosaicism and numerical abnormality therefore were both present. Dual-color FISH revealed karyotype of nuc ish(DXZ1× 1, SRY× 1)[390/400]/(DXZ1× 2, SRY× 1) [10/400]. Four-color FISH showed that the abnormal chromosome 15 has derived from a pseudodicentric (Y;15) translocation, and that the breakpoint on Y chromosome was located at Yq12. G-banding and FISH results confirmed that the karyotype was 45,X,der(15)(?::p11.2→ qter)dn.ish psu dic(15;Y)(p11.2;q12)(D15Z1+ , SNRPN+ , PML+ ; SRY+ , DYZ3+ , DYZ1+ ). Microdeletion of AZFc combined with sY254 deletion was detected by multiplex PCR., Conclusion: Cytogenetic and molecular genetic analysis of the patient has indicated meiotic disturbances with spermatogenetic arrest resulting from a pseudodicentric chromosome derived from Y;15 translocation and spermatogenesis dysfunction resulting from partial deletion of AZFc region.

Objective: To evaluate idic(Yp) in genetic diagnosis by examining 1 infertile man and 1 prenatal fetus using cytogenetic and molecular techniques., Methods: Following conventional chromosome preparation, we performed G- and C-banding karyo. typing and fluorescence in situ hybridization (FISH). Then we extracted genomic DNA using standard procedures and analyzed it by array-CGH and multiplex ligation-dependent probe amplification (MLPA)., Results: Both cases were diagnosed as 45, X/46, X, idic (Yp11.31) mosaicism. The man showed 2 intact copies of Yp11.31-q12 (chrY:2, 710, 250-57, 428, 567, SRY, ZFY, UTY and AZF), and the prenatal fetus exhibited similar findings except a paternal deletion in the AZFc region., Conclusion: idic(Y) (p11.31) causes short stature and male infertility. Array-CGH and MLPA can improve the accuracy of the diagnosis of 45, X/46, X, idic (Y) mosaicism, which may contribute to the studies of the phenotype-genotype correlation and clinical genetic counseling.

Objective: To investigate the characteristics of null allele for 17 Y-chromosomal short tandem repeats (Y-STR) loci in a group of infertile males., Methods: Two hundred thirty six infertile males featuring non-obstructive azoospermia and severe oligozoospermia were analyzed with an AmpFISTR ((R)) Yfiler (TM) kit. Deletions of azoospermia factor (AZF) fragments were confirmed with Y chromosome sequence-tagged sites (STSs) analysis using modified multiplex PCR., Results: The overall prevalence of AZF microdeletions was 16.95% (40/236). In the non-obstructive azoospermia group, 13 cases had AZFc deletion, 6 cases had AZFb+c deletion, 2 cases had AZFa deletion, 1 case had AZFb deletion. In the severe oligozoospermia group, 17 cases had AZFc deletion and 1 had AZFb deletion. No AZFa+b+c deletion was detected. Forty cases showed null alleles by scanning of the 17 STR loci. Deletions of DYS438, DYS439, DYS437, DYS389I and DYS389II were found in the 2 cases with AZFa deletion. In patients with AZFb deletion, DYS392 and DYS385a/b were found deleted. Deletions of DYS448 were detected in all of the 30 cases with AZFc deletion. Deletions of DYS392, DYS385a/b, and DYS448 were found in 6 cases with AZFb+c deletion., Conclusion: Deletions of the Y chromosome AZF regions are associated with azoospermia and severe oligozoospermia. Null allele due to complete absence of AZFa, AZFb and AZFc regions may lead to misinterpretation in the sexual assault cases. Revealing the locus heterogeneity in male infertility population can enrich the Y-STR database and facilitate interpretation STR data in forensic DNA testing.

Dongxiang is one of special ethnic groups of Gansu Province. Their language is one of the Mongolian languages of Altai language family. And their origin has long been controversial. The results of Cluster analyses (multidimensional scaling analysis, dendrograms, principal component analyses, and networks) of Dongxiang population and other ethnic groups indicated that Dongxiang people is much closer to the Central Asian ethnic groups than to the other Mongolian. Admixture analyses also confirmed the result. This suggests that Dongxiang people did not descend from Mongolian, but from the Central Asian ethnic groups that have spoken Persian or Turkic language. This mismatch between paternal genetic lineage and language classification might be explained by the elite-dominance model. The ancestral populations of Dongxiang could be the Central Asian ethnic groups assimilated by Mongolian in language and culture.

Y chromosome is a male-specific paternal inherited chromosome. The STR markers on Y chromosome have been widely used in forensic practices. This article summarizes the characteristics of Y-STR and some factors are considered of selecting appropriate Y-STR markers for Chinese population. The prospects of existing and potential forensic applications of Y-STR profiles are discussed including familial excluding, familial searching, crowd source deducing, mixture sample testing, and kinship identifying. The research, development, verification of Y-STR kit, Y-STR mutation rate, and search software are explored and some suggestions are given.

In order to study the molecular genetic structure of Mulam ethnic group in Guangxi, China, Y chromosome and mitochondrial DNA(mtDNA)polymorphisms were genotyped. High frequencies of the Y chromosome haplogroups O1a1-P203 and O2a1*-M95 were found in Mulam, exhibiting a pattern similar to the neighboring indigenous populations, especially the Daic populations. MtDNA lineages F1a, M*, B4a, B5a, M7b, and N9a were found in Mulam, which always present at high frequencies among the populations of East Asia. Mulam exhibits genetic characteristics of southern Chinese in both paternal and maternal lineages. Multiplex detection of the 17 Y-STR loci and mtDNA HVS-I revealed the distribu-tion of highly genetic diversity in Mulam, which would have potential application in population genetics and forensic practice.

133 candidate Y-STR loci were selected from NCBI STS database or by bioinformatics analysis in human Y-chromosome sequence, and were screened among 48 DNA samples around the world. Forty-one Y-STRs with high allelic frequency were validated, 36 of which were first reported. Two hundred haplotypes of the 41 STRs were identified among 200 randomly sampled male individuals in Shanghai, indicating 100% inter-individual discrimination. By network analysis of haplotypes of the 41 STRs among nine Jiang-surname male individuals with no consanguinity within 5 generations from a Jiang-surname individual gathering at Jiangshan, Zhejiang Province, and 7 Jiang-surname male individuals from the random shanghai population, 6 Jiang-surname individuals from Jiangshan were close with only 2-4 STR locus difference. These 41 Y-STR loci provide enough information by which individuals from each other with different early modern family origin can be effectively distinguished. This will promote studies on identification of non-lineal relationship in forensics, ancestry location of oversea Chinese, the surname origin and evolution, origin and migration of modern humans and many other studies of Contemporary Anthropology.

Objective: To investigate Y chromosome microdeletions in severe oligospermia men with varicocele., Methods: We randomly selected 100 cases of severe oligospermia with left varicocele (sperm concentration <5 x 10(6)/ml, group 1), 100 cases of mild oligospermia with left varicocele (sperm concentration 10 -20 x 10(6)/ml, group 2), 100 cases of idiopathic infertility with severe oligospermia (group 3), 100 cases of idiopathic infertility with moderate oligospermia (group 4) and 30 normal fertile men as controls (group 5). We used polymerase chain reaction (PCR) technology to screen 9 sequence tagged sites (STS) of the AZF a, b and c regions and detect Y chromosome microdeletions., Results: AZF microdeletions were found in 19 patients in group 1 (19%) and 11 in group 3 (11%), with a higher rate in the former than in the latter, but not in the other three groups., Conclusion: Screening of Y chromosome microdeletions should be performed before the treatment of severe spermatogenesis with varicocele.

Objective: To investigate the relationship between Y chromosome microdeletions and human spermatogenesis in infertile men with varicocele (VC)., Methods: We divided 174 infertile VC patients into groups A (with azoospermia, n = 47) , B (with severe oligozoospermia, n=57) and C (with mild oligozoospermia, n=70), and enlisted 28 fertile males and 26 fertile females as normal controls. We collected DNA from the peripheral blood, amplified 6 sequence tagged sites in AZFa, AZFb and AZFc using multiplex PCR technique. Then we separated and scanned the amplified products by agarose gel electrophoresis to identify microdeletions and their types in comparison with the controls., Results: Y chromosome microdeletions were observed in 12.64% of the patients (22/174), 11 cases in group A and the other 11 in group B, but none in group C and the normal controls. The differences were statistically significant (P<0.05). In group A, 6 of the microdeletion cases were in the AZFc region, 1 in the AZFa region, 2 in the AZFb region and 2 in both AZFb and AZFc regions, while in group B, 8 cases were in the AZFc region, 2 in the AZFb region and 1 in both AZFb and AZFc regions., Conclusion: Infertility is correlated to Y chromosome microdeletions in VC patients. Y chromosome microdeletion screening should be performed for infertile VC patients, especially for those with azoospermia or severe oligozoospermia.

The Y chromosome contains genes closely related to male gonadal development and spermatogenesis. The azoospermia factor (AZF) is a gene on the long arm of the Y chromosome that regulates spermatogenesis, and its deletion can induce spermatogenic arrest and consequently male infertility. Most researchers subdivide AZF into AZFa, AZFb and AZFc, and some believe there to be another region, AZFd, between AZFa and AZFb. Different AZF deletions lead to different phenotypes. AZFc deletion, as the commonest type that attracts widespread attention of researchers, includes complete AZF deletion and partial AZF deletion, and the latter mainly consists of gr/gr deletion and b2/b3 deletion. The gr/gr deletion can cause infertility in some areas or in human species. The influence of b2/b3 deletion on spermatogenesis has not been confirmed, but its wide spread in haplogroup N has distribution scientists' attention. This review outlines the structures, candidate genes and deletions of AZF, especially AZFc, along with their relationship with spermatogenesis, so as to provide a theoretical basis for clinical prenatal diagnosis and treatment of infertility.

Objective: To characterize molecular and cytogenetic abnormalities in six 46, XX males, and to investigate the clinical manifestations and underlying mechanisms in such patients., Methods: Clinical data of six XX male patients were collected. Karyotyping, multiple polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) were utilized to detect and locate the sex determining region (SRY) gene., Results: PCR and FISH showed that all patients were SRY-positive XX males. All patients have their SRY gene located at the tip of derivative X chromosomes, which have resulted from translocation between short arms of X and Y chromosomes. High resolution karyotyping at 550-750 band level has revealed that the translocation breakpoints were at Xp22.33 and Yp11.2 in three patients. In the remaining patients, the breakpoints were either at Xp22.32 and Yp11.31 or Xp22.31 and Yp11.2. The breakpoints at Xp22.32, Xp22.31 and Yp11.31 were rarely reported. Genotype-phenotype correlation analysis indicated that the clinical manifestations were age-specific. Four adult patients have come to clinical attention due to infertility, with typical features including azoospermia and testis dysgenesis, whereas poorly developed secondary sexual characteristics and short stature were main complaints of adolescence patients, and short stature was the sole symptom in a child patient., Conclusion: Combined karyotyping, PCR and FISH are important for the analysis of XX males. Particularly, high resolution karyotyping is valuable for the refinement of chromosome breakpoints and detailed analysis of genotype-phenotype correlation.

To investigate the genetic polymorphisms of 17 Y-chromosomal short tandem repeats(Y-STR) loci in She ethnic population from Fujian province, and to evaluate their forensic application values and genetic relationship with other 11 populations, 152 unrelated male individuals of She ethnic population in Fujian were used to determine the distribution of allele frequencies and haplotypes by using Y-filerTM System. Cluster analysis and phylogenic trees were applied to show the genetic distance among the populations. As a result, 50 haplotypes were found in DYS385a/b loci, and 3～11 alleles were found in the rest 15 Y-STR loci. The GD value was from 0.4037(DYS391) to 0. 9725(DYS385a/b). This study has also revealed "off-ladder" alleles at several Y-loci, namely DYS448, DYS393, DYS458 and DYS635, and several occurrences of duplications at the DYS385a/b, DYS19 and DYS390 loci. One hundred and forty-four haplotypes were found in 17 Y-STR loci, of which 138 were unique, 5 were found in 2 individuals, 1 was found in 4 individuals, and the observed haplotypes diversity value was 0.9990. Comparing with 11 populations, the genetic distance between She ethnic and Han population in Zhejiang was the smallest (0.0042), while it was the largest between She ethnic and Tibet ethnic population (0.2380). Cluster analysis and phylogenetic tree both demonstrated that genetic distance between She ethnic and several south Han populations is closer than between She ethnic and non-Han populations. Multiplex detection of the 17 Y-STR loci revealed a highly polymorphic genetic distribution, which would be very powerful for establishing a Y-STR database, for population genetics and forensic practice.

Objective: To investigate the breakpoints of the azoospermia factor c (AZFc) microdeletion in Chinese Han population., Methods: We detected 9 sequence tagged sites (sY84, sY86, sY127, sY134, sY152, sY145, sY255, sY254 and sY157) to confirm AZFc microdeletions in the Y chromosome for patients with severe oligozoospermia or non-obstructive azoospermia by multiplex polymerase reaction. To locate the breakpoints of AZFc microdeletions, we analyzed 192 patients with sY255, sY254 and sY157 dele- ted by detecting sY1191, sY1197, sY1054, sY1125 and sY1206, respectively., Results: Five breaking patterns were found in the 192 patients with sY255, sY254 and sY157 deleted, among which the common ones were sY1197(+), sY1191(-), sY1054(-), sY1206(-) and sY1125(+), which accounted fro 54.17% (104/192), sY1197(+), sY1191(+), sY1206(-), sY1054(-) and sY1125(+), which constituted 28.12% (54/192), sY1197(+), sY1191(-), sY1206(-), sY1054(+) and sY1125 (+), which made up 14.58% (28/192). The proximal breakpoint located between sY1197 and sY1191 was 70.83% of AZFc microdeletions, and the distant breakpoint located between sY1054 and sY1125 was 82.29%., Conclusion: There are 5 breaking patterns of AZFc microdeletions in Chinese Han population, the proximal and distant breakpoints mostly located at the replicons b2 and b4, respectively.

Objective: To investigate the prevalence and subtypes of microdeletions in azoospermia factor (AZF) region in infertile men from Sichuan in order to correlate genotypes with phenotypes., Methods: Multiplex-PCR was used to detect sequence tagged sites (STS) of AZF microdeletions in 1011 infertile men including 713 cases of non-obstructive azoospermia and 298 cases of severe oligospermia., Results: The overall prevalence of microdeletions was 10.48% (106/1011), and the deletion rates were 11.08% (79/713) in non-obstructive azoospermia and 9.06% (27/298) in severe oligospermia. Complete AZFa or AZFb deletions were associated with azoospermia, whereas AZFc deletion (60.38%) was the most frequent deletion. The deletions were associated with variable spermatogenic phenotypes, and 37.50% of the patients with a deletion had sperms in the ejaculate. A mild decline in sperm concentration was found in two cases with partial AZFb deletion and one case with partial AZFb-c deletion., Conclusion: Deletions of the AZFc region were most commonly found in our patients. All cases with complete AZFa or AZFb deletions and a proportion of cases with AZFc deletion were associated with azoospermia. Our study has provided more insight into the genotype-phenotype correlation, and confirmed that Yq microdeletion screening has a significant value for the diagnosis for male infertility.

Objective: To determine the allelic sequences and genetic polymorphism of six short tandem repeats (STRs) loci on Y chromosome, including DYS441, DYS442, DYS443, DYS444, DYS445 and DYS446 in Chinese Korean ethnic males from Yanbian region of Jilin province, China, and to construct a preliminary database., Methods: Allele frequencies of the six STR loci in 205 Chinese Korean ethnic individuals were analyzed by multiplex polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE)., Results: Respectively, 8, 7, 7, 5, 6 and 9 alleles were detected for each of the locus. Together they have formed 151 haplotypes, with a diversity of 0.9937., Conclusion: The six STR loci included in this study were found to be highly polymorphic, and may provide useful markers for genetic analysis.