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Research Question: What is the incidence of complex mosaic in preimplantation genetic testing (PGT) blastocysts and can it be managed in clinical practice?, Design: A retrospective study of PGT cycles conducted between January 2018 and October 2019 at a single centre. Biopsies of blastocysts were collected and analysed by next-generation sequencing (NGS). Complex mosaic blastocysts were defined as those with three or more mosaic chromosomes. The cryopreserved complex mosaic blastocysts underwent a second round of biopsy, NGS analysis and vitrification. The euploid blastocysts identified by the re-biopsy were warmed again for embryo transfer. The main outcomes included the prevalence of the complex mosaic and the ongoing pregnancy rate., Results: The prevalence of the complex mosaic was 2.4% (437/17,979). The prevalence of the complex mosaic was not associated with maternal age and morphological quality. A total of 89 complex mosaic blastocysts underwent re-biopsy and 96.6% (86/89) survived the first warming. For the re-biopsy samples, 61.6% (53/86) were euploid. The poor-quality blastocysts had higher rates of aneuploidy compared with good-quality blastocysts. The survival rate for blastocysts undergoing the second warming was 100% (18/18) and resulted in an ongoing pregnancy rate of 38.9% (7/18) as well as the birth of six healthy infants., Conclusion: Re-biopsy may rescue blastocysts with development potential for transfer and improve the cumulative pregnancy rate per stimulation cycle in patients containing complex mosaic blastocysts., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Preimplantation genetic testing for aneuploidies has increasingly been employed for embryo selection, resulting in a recent surge in mosaic embryos. According to the cytogenetic results, which types of mosaic embryo survive early pregnancy, progress to the second trimester and finally result in a live birth?, Design: This study evaluated 30,587 pregnant women undergoing amniocentesis from January 2004 to March 2020 at the cytogenic centre of Kaohsiung Chang Gung Memorial Hospital. Samples from amniocentesis were cultured using the in-situ method. The types and distribution of level III chromosomal mosaicism (two or more cells with the same abnormality in two or more colonies and both culture dishes, clinically referred to as 'true mosaicism') were retrospectively reviewed., Results: Among the 30,587 women, 78 cases (0.26%) of level III chromosomal mosaicism were identified. The types of chromosomal mosaicism were classified as sex chromosome mosaicism (SCM), autosomal chromosome mosaicism (ACM) and marker chromosome mosaicism (MCM), with SCM, ACM and MCM accounting for 58.97%, 32.05% and 8.97% of cases, respectively. The most common mosaic cell lines were monosomy X and trisomy 21. The most common mosaic cell line progressing to live birth was monosomy X., Conclusions: Mosaic monosomy X and trisomy 21 are the most common cell lines of true mosaicism determined by amniocentesis. Monosomy X mosaicism is the most common cell line in live births. For women considering the transfer of these types of mosaic embryo in a circumstance where euploid embryos are unavailable, clinicians should provide careful prenatal counselling, detailed ultrasonography and amniocentesis., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Are intrinsic or extrinsic factors associated with embryo mosaicism prevalence in IVF cycles?, Design: Retrospective cohort study of preimplantation genetic testing for aneuploidy (PGT-A) cycles carried out at a university-affiliated IVF clinic between October 2017 and October 2019. Trophectoderm biopsies were analysed by next generation sequencing. Mosaicism prevalence, type of anomaly and the chromosomes involved were analysed. Intrinsic and extrinsic factors potentially inducing mosaicism were studied: maternal and paternal age, antral follicle count, cumulus-oocyte complexes retrieved, female body mass index, PGT-A indication, sperm concentration, total dosage of gonadotrophins, embryo quality and day of blastocyst formation, single-step commercial media used and biopsy operator., Results: Overall prevalence of mosaicism in our PGT-A setting was 13.9%. In segmental mosaicism, larger chromosomes tended to be more affected, which was not observed in whole-chromosome mosaicism. Additionally, segmental mosaicism was mostly observed in monosomy (69.6%; P < 0.01) compared with whole-chromosome mosaicism (49.7% monosomies versus 50.3% trisomies; P = 0.83). Although a high inter-patient variability was observed, only paternal age showed a positive association with mosaicism (adjusted OR 1.26, 95% CI 1.02 to 1.54) among the analysed variables., Conclusions: Our results suggest remarkable differences in the mechanisms generating segmental and whole-chromosome mosaicism, indicating that they may deserve different consideration when studying them and when prioritizing them for transfer. Male factor seems to be associated with mosaicism and may be worthy of specific assessment in future studies., (Copyright © 2020 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Objective: To examine the relationship between the fraction of cell-free DNA (cfDNA) affected by aneuploidy compared to the overall fetal fraction of a prenatal screening specimen and its effect on positive predictive value (PPV)., Method: CfDNA specimens positive for trisomy 13, 18, and 21 with diagnostic outcomes were analysed over a 22-month period in one clinical laboratory. For each positive specimen, a "mosaicism ratio" (MR) was calculated by dividing the fraction of cfDNA affected by aneuploidy by the overall fetal fraction of the specimen. PPVs were calculated and analyzed based on various MR ranges., Results: Trisomy 13 was the aneuploidy most commonly seen in mosaic form, followed by trisomy 18 and trisomy 21. Significant differences in positive predictive values were noted for all three trisomies between samples with an MR in the "mosaic" versus "non-mosaic" range, as well as between results classified as "low-mosaic" versus "high-mosaic.", Conclusion: PPVs may be influenced, in part, by the mosaicism ratio associated with a particular result. The data generated from this study may be useful in providing more personalized risk assessments for patients with positive cfDNA screening results., (© 2020 Laboratory Corporation of America Holdings. Prenatal Diagnosis published by John Wiley & Sons Ltd.)

Objective: To evaluate the prevalence of mosaicism in chorionic villus sampling (CVS) samples after chromosomal microarray (CMA) and clinical outcome of pregnancies affected by confined placental mosaicism., Method: We retrieved all results from CMA, array-based comparative genomic hybridization, on CVS samples from January 2011 to November 2017 from Central and North Denmark Regions. Mosaic results from uncultured chorionic villi, cytotrophoblasts and mesenchymal cells, after CVS and follow-up on amniocytes, fetal tissue, or postnatal blood were studied and matched with clinical data from The Danish Fetal Medicine Database., Results: Prevalence of mosaicism was 93 out of 2,288 (4.1%) CVS samples of which 17 (18.3%) concerned submicroscopic copy number variations (CNVs) <10 Mb. Follow-up analyses were performed in 62 cases. True fetal mosaicism (TFM) was confirmed in 18.4% (7/38) when mosaicism involved whole chromosome aneuploidy and in 25.0% (6/24), when involving a CNV (P = .59). Median birth weight z-score was higher in cases of confined placental mosaicism for a CNV (0.21) than cases involving whole chromosomes (-0.74) (P = .02)., Conclusion: Prevalence of mosaicism in CVS samples is higher after CMA on uncultured tissue than after conventional karyotyping on cultured tissue. The risk of TFM is equally high in cases of mosaicism for CNVs and whole chromosomes., (© 2019 John Wiley & Sons, Ltd.)

Aim: The aim of this study is to summarize the outcomes of transfers of mosaic embryos, which were classified according to guidelines and in strong collaboration of reproductologists, clinical geneticists and patients approved as suitable for transfer. Material and Methods: Retrospective data were collected from 70 patients from a private IVF center to whom embryos with mosaic changes in chromosomal material were transferred from 2015 to 2019. Results and Conclusion: Implantation outcomes and continuing pregnancies showed slight differences, when compared to fully normal embryos. Artifacts have to be differentiated from undeniable aberrations, and correct interpretation of results must be done with following patient counselling and prenatal testing if necessary.

Objective: To investigate the effects of parental mosaicism on their preimplantation embryos., Design: Case series., Setting: An institute for reproductive and stem cell engineering., Patient(s): Sixty-eight mosaic couples., Intervention(s): Assisted reproduction with preimplantation genetic testing (PGT)., Main Outcome Measure(s): Karyotypes, embryo-related chromosomal abnormalities, and PGT results., Result(s): A total of 209 embryos were obtained from 68 mosaic couples, and 153 (73.21%) of 209 of the total embryos were obtained from 55 mosaic couples with abnormal sex chromosome numbers. Of these 153 embryos, 2 (1.31%) had an abnormal copy number of X chromosome, 1 had mosaicism with 46,XN,+X(mosaic, 40%), 1 (0.65%) had an extra Y chromosome, 3 (1.96%) exhibited both X chromosomal and autosomal abnormalities, and 4 (2.61%) exhibited de novo X chromosome structural abnormalities. A total of 56 (26.79%) of 209 embryos were obtained from mosaic couples (n = 13) with abnormal autosomal structures. Notably, of these 56 embryos, 5 (8.93%) had a 16q21-q24.3 copy number abnormality related to the parental karyotype, with a fragile site at 16q22; 5 (7.14%) exhibited 46,XX,dup(8p23.1-8p11.21) and 46,XY,del(8p22-8p11.21), which were related to the parental karyotype; and 10 (17.86%) were de novo chromosome abnormalities., Conclusion(s): Our data demonstrate that the risk of embryo-related chromosome abnormalities in mosaic patients with abnormal sex chromosomes is very low. Therefore, PGT may not need to be recommended for mosaic patients with abnormal copy numbers of sex chromosomes, especially for patients with financial difficulties. By contrast, the mosaic patients with structural abnormalities of autosomes may have a relatively high risk of abnormal embryos with an unbalanced segment of the involved chromosomes. Thus, PGT is highly recommended for mosaic patients with autosomal structure abnormalities, especially those with a fragile site at 16q22., (Copyright © 2019 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To assess the impact of non-invasive prenatal testing (NIPT) on trends in the prenatal diagnosis of sex chromosome aneuploidy (SCA) in a population with >73,000 annual births., Method: Retrospective population-based cohort study from 1986-2016 of all women undergoing prenatal diagnosis before 25 weeks gestation in the Australian state of Victoria. Statistical significance was tested using the chi-square test for trend or proportions., Results: There were 2,043,345 births and 842 SCA diagnoses from 1986-2016. The percentage of prenatal diagnostic tests leading to a SCA diagnosis increased significantly from 0.95% in 2010 to 2.93% in 2016 (p < 0.001) but due to a concurrent decline in testing, the annual prenatal diagnosis rate of SCA remained stable at 4.4/10,000 births. Among confirmed fetal SCAs the most common indication for testing in 1986 was advanced maternal age (63%); in 2016 it was high risk NIPT (49%)., Conclusion: SCAs now make up an increasing proportion of prenatal diagnostic results but due to the overall decline in diagnostic testing, the prenatal prevalence as a percentage of births remained steady. The ascertainment of fetal SCA has evolved from an incidental finding after testing for increased risk of trisomy 21, to a diagnosis obtained after suspected SCA on NIPT., (© 2018 John Wiley & Sons, Ltd.)

Background: Mosaic loss of chromosome Y (mLOY) can occur in a fraction of cells as men age, which is potentially linked to increased mortality risk. Smoking is related to mLOY; however, the contribution of air pollution is unclear., Objective: We investigated whether exposure to outdoor air pollution, age, and smoking were associated with mLOY., Methods: We analyzed baseline (1989-1993) blood samples from 933 men ≥65 years of age from the prospective Cardiovascular Health Study. Particulate matter ≤10 μm (PM 10 ), carbon monoxide, nitrogen dioxide, sulfur dioxide, and ozone data were obtained from the U.S. EPA Aerometric Information Retrieval System for the year prior to baseline. Inverse-distance weighted air monitor data were used to estimate each participants' monthly residential exposure. mLOY was detected with standard methods using signal intensity (median log-R ratio (mLRR)) of the male-specific chromosome Y regions from Illumina array data. Linear regression models were used to evaluate relations between mean exposure in the prior year, age, smoking and continuous mLRR., Results: Increased PM 10 was associated with mLOY, namely decreased mLRR (p-trend = 0.03). Compared with the lowest tertile (≤28.5 μg/m 3 ), the middle (28.5-31.0 μg/m 3 ; β = -0.0044, p = 0.09) and highest (≥31 μg/m 3 ; β = -0.0054, p = 0.04) tertiles had decreased mLRR, adjusted for age, clinic, race/cohort, smoking status and pack-years. Additionally, increasing age (β = -0.00035, p = 0.06) and smoking pack-years (β = -0.00011, p = 1.4E-3) were associated with decreased mLRR, adjusted for each other and race/cohort. No significant associations were found for other pollutants., Conclusions: PM 10 may increase leukocyte mLOY, a marker of genomic instability. The sample size was modest and replication is warranted., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To present the calculated frequencies, male to female sex-ratio, and modes of ascertainments in different levels of chromosomal mosaicism (CM) detected at amniocentesis., Materials and Methods: This's a 10-years retrospective study between January 2008 and December 2017 and there were 13,752 cases of amniocentesis performed in MacKay Memorial Hospital, Taipei, Taiwan. Eight hundred and thirty four cases of CM were collected in this study. We reviewed their types of chromosomal abnormalities of mosaicism, the modes of ascertainment (including: advanced maternal age, abnormal ultrasound findings, abnormal maternal serum screening result, and other reasons), maternal age, gestational age at amniocentesis, fetal gender, and perinatal findings. After amniocentesis, in situ culture was performed and the results of karyotype with CM were divided in to three levels., Results: In our sample of 13,752 amniocentesis, 834 cases with all levels of CM were collected in this study. Of them, there were 562 cases (4.09%) with level I mosaicism, 207 cases (1.51%) of level II mosaicism, and 65 cases (0.47%) of level III mosaicism (Table 1). In the group of advanced of maternal age (AMA), their calculated frequencies, 4.18% in level I, 1.46% in level II and 0.41% in level III, were very similar to those in total cases (p value = 0.206) without statistical significance. In the group of abnormal ultrasound findings, the calculated frequency was much higher in level III (0.87%), however, there was no statistical significance because of the small numbers of level III. In our cases of amniocentesis, the case numbers of male case (50.20%) is very similar to female (49.80%), and the male to female ratio was 1.01. But, we found more cases of male with CM (444 cases) than female (390 cases). The sex-ratio in different levels' calculated frequencies of CM showed similar in level I, and male prevalence was found in level II and III with statistical significance (p value = 0.022). The male prevalence also revealed in both numerical and structural abnormalities in level II and level III, but no difference in the cases of level I., Conclusion: In conclusion, our observation showed a novel finding of higher male prevalence of CM in level II and III, and both in numerical and structural abnormalities. It's consistent with the theory of better survival in male embryo after partial self-correction of initial chromosomal aberrations, male-specific selection against chromosomal abnormalities., (Copyright © 2018. Published by Elsevier B.V.)

Objective: Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE) are related by clinical and serologic manifestations as well as genetic risks. Both diseases are more commonly found in women than in men, at a ratio of ~10 to 1. Common X chromosome aneuploidies, 47,XXY and 47,XXX, are enriched among men and women, respectively, in either disease, suggesting a dose effect on the X chromosome., Methods: We examined cohorts of SS and SLE patients by constructing intensity plots of X chromosome single-nucleotide polymorphism alleles, along with determining the karyotype of selected patients., Results: Among ~2,500 women with SLE, we found 3 patients with a triple mosaic, consisting of 45,X/46,XX/47,XXX. Among ~2,100 women with SS, 1 patient had 45,X/46,XX/47,XXX, with a triplication of the distal p arm of the X chromosome in the 47,XXX cells. Neither the triple mosaic nor the partial triplication was found among the controls. In another SS cohort, we found a mother/daughter pair with partial triplication of this same region of the X chromosome. The triple mosaic occurs in ~1 in 25,000-50,000 live female births, while partial triplications are even rarer., Conclusion: Very rare X chromosome abnormalities are present among patients with either SS or SLE and may inform the location of a gene(s) that mediates an X dose effect, as well as critical cell types in which such an effect is operative., (© 2017, American College of Rheumatology.)

Background: Advanced paternal and/or maternal age is a classic risk factor for Down syndrome. The aim of the study was to investigate the frequency of Down syndrome types in children and its association with maternal and paternal age in Bosnia and Herzegovina., Subjects and Methods: The cross sectional, observational study included 127 children, 49 girls and 78 boys, aged 1-180 months suspected to have Down syndrome, admitted to the Centre for Genetics, Faculty of Medicine University of Sarajevo, for cytogenetic analysis and differential diagnosis of Down syndrome during the period from January 2010 to May 2015. Standard method of 72 hours cultivation of peripheral blood lymphocytes has been applied. The accepted level of statistical significance was p<0.05., Study Results: The most common type of Down syndrome was standard trisomy (86.6%), comparing to translocation and mosaicism (7.1%; 6.3%, respectively). The highest frequency of Down syndrome cases was in mother and father's group from 30-39 years old (57; 57 children, respectively) compared to mother and father's groups with younger than 30 (44; 29, respectively) and 40 and older (26; 41, respectively). The significant difference was found in maternal age between translocation and mosaicism groups (p=0.036). Difference between parental years and type of Down syndrome was significant when Standard trisomy 21 and translocation (p=0.045), as well as mosaicism and translocation (p=0.036), were compared., Conclusion: The most common type of Down syndrome was standard trisomy 21, with highest occurrence in parents from 30 to 39 years old. Parents were the youngest in translocation group. Obtained results suggest that multidisciplinary approach to identifying the trigger for trisomy appearance and the influence of maternal age is required.

This study describes the cytogenetic characteristics of 7,133 trisomy 21 (Tri21) identified from 247,818 consecutive postnatal cases karyotyped in a single reference laboratory in China for a period of 4 years. The average detection rate of Tri21 is 2.88% ranging from 3.39% in 2011 to 2.52% in 2014. The decreased detection rates over the years might reflect a possible impact of noninvasive prenatal testing applied rapidly in China and elective termination of affected pregnancies. 95.32% of the Tri21 karyotypes are standard Tri21, 4.53% are Robertsonian Tri21, and less than 1% are other Tri21 forms. There are more mosaic Tri21 in older children and adults, consistent with previous observations that clinical features in individuals with mosaic Tri21 are generally milder and easily missed during perinatal period. The male/female (M/F ratio) for the total 7,133 Tri21 cases and for the 6,671 cases with non-mosaic standard Tri21 are 1.50 and 1.53 respectively, significantly higher than the 0.93 for all the 247,818 cases we karyotyped, the 1.30 for the Down syndrome (DS) identified during perinatal period in China, and the 1.20 for the livebirth in Chinese population. In contrast, the mosaic standard Tri21 case has a significantly lower proportion of males when compared with the non-mosaic standard Tri21, indicating different underlying mechanisms leading to their formations. Opposite M/F ratios in different subtypes of ROB Tri21 were observed. A long list of rare or private karyotypes where Tri21 are concurrently present was identified. The large collection of Tri21 cases with a diversity of clinical findings and a wide age range allowed us to determine the frequency of the different karyotypes of Down syndrome in China, given the fact that this kind of national epidemiological data is lacking currently.

Objective: The risk of clinical consequences in prenatal cases with de novo small supernumerary marker chromosomes (sSMC), often in mosaic conditions, is not easy to predict, which results in difficulties in genetic counseling., Method: In this study, we evaluated the frequency, the chromosomal origin, and the clinical indication of 104 de novo sSMC detected in a monocenter survey on the basis of 143,000 consecutive prenatal diagnoses, and we assessed the reliability of molecular cytogenetics technologies for sSMC characterization., Results: We detected a de novo sSMC frequency of 0.072%. Its incidence in advanced maternal age group is statistically different from that found in maternal anxiety indication (<35 years old). A higher prevalence of mosaicism in chorionic villi sampling (CVS) than in amniotic fluids was also revealed related to confined placental mosaicisms. The risk of confirmation in amniotic fluids of mosaics previously revealed at CVS was 33.3%. No uniparental disomy conditions were found when imprinted chromosomes were involved in the occurrence of de novo sSMC. The majority of de novo sSMC were acrocentric derived-chromosomes, and a neocentromere formation was observed in one pregnancy., Conclusion: Our data support that array comparative genomic hybridization has improved sSMC characterization and demonstrate its utility in supporting genetic counseling. We propose a workflow for de novo sSMC characterization., (© 2014 John Wiley & Sons, Ltd.)

Objective: To determine whether men with Klinefelter syndrome (KS) have the same phenotype as men with mosaic KS., Design: Subject identification via prospectively collected database., Setting: Male infertility specialty clinic., Patient(s): Men undergoing a fertility evaluation from 2005 to 2012 at a single male infertility specialty clinic and having a karyotype demonstrating KS (mosaic or non-mosaic)., Intervention(s): None., Main Outcome Measure(s): Testicular size, and semen and hormone parameters, genetic evaluation, and signs of testosterone (T) deficiency using validated questionnaires., Result(s): Of 86 men identified with KS, 6 (6.7%) were mosaic KS, and 80 (93.3%) were non-mosaic KS. Men with mosaic KS had lower baseline luteinizing hormone (LH) levels (10.31 IU/L ± 5.52 vs. 19.89 IU/L ± 6.93), lower estradiol levels (58.71 ± 31.10 pmol/L vs. 108.57 ± 43.45 pmol/L), larger mean testicular volumes (11 ± 7.3 mL vs. 6.35 ± 3.69 mL), and a higher mean total sperm count (4.43 ± 9.86 M/mL vs. 0.18 ± 1.17 M/mL). A higher proportion of men with mosaic KS had sperm in the ejaculate: 3 (50%) of 6 versus 3 (3.75%) of 80. The Sexual Health Inventory for Men (SHIM) and Androgen Deficiency in the Aging Male (ADAM) questionnaire scores were not different between groups., Conclusion(s): Men with mosaic KS seem to be more well androgenized than their non-mosaic KS counterparts, both with respect to hormones and sperm in the ejaculate., (Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study is to present the incidence, prenatal and postnatal findings, and modes of ascertainment in chromosomal deletions detected at amniocentesis., Materials and Methods: We reviewed all the cases with chromosomal deletions, which were detected by amniocentesis in Mackay Memorial Hospital, Taipei, Taiwan, between January 1987 and December 2012. Data on the locations and types of deletion, reasons for performing amniocentesis, maternal age, gestational age at amniocentesis, fetal karyotypes, inheritance of deletions, and relative prenatal findings were collected., Results: Amniocentesis was performed in 33,305 cases within this period of time. Among these, 31 cases of chromosomal deletions were considered for the study. The mean gestational age at amniocentesis was 21.0 weeks (range from 15 weeks to 32 weeks) and the mean maternal age at amniocentesis was 32.1 years (range from 26 years to 37 years). Nineteen cases (61.3%) manifested fetal structural abnormalities on ultrasound, nine (29.0%) presented no ultrasound abnormalities, and three had an unknown status. The main modes of ascertainment included abnormal ultrasound findings in 10 cases (32.2%), advanced maternal age in 11 cases (35.5%), abnormal maternal serum screening results in six cases (19.6%), and other reasons in four cases (13.0%). Of the 27 cases with known inheritance, the deletion was inherited in two (6.6%) and de novo in 25 (92.6%). Males accounted for 11 (35.5%) and females for 20 (64.5%) cases. Chromosomal deletions are more often to occur in chromosomal 5(4 cases, 12.9%), chromosomal 18 (4 cases, 12.9%), chromosomal 4 (3 cases, 9.7%), chromosomal 7 (3 cases, 9.7%), chromosomal 10 (3 cases, 9.7%), chromosomal 11 (3 cases, 9.7%), and chromosomal 1 (2 cases, 6.5%). There were four cases of chromosomal mosaicism: two involved chromosome 5, one involved chromosome 10, and one involved chromosome 18. Twenty-three cases (74.2%) had terminal deletions and the other eight cases (26.7%) had interstitial-type deletions., Conclusion: In summary, we have presented the results of prenatal diagnosis for chromosomal deletions using amniocentesis. Chromosomal deletions are more likely to occur in females and more often in chromosomal 5p and 18q. Prenatal diagnosis at amniocentesis is frequently associated with advanced maternal age, abnormal ultrasound findings, and abnormal maternal serum screening. The frequency of ascertainment in chromosome deletion seems to be directly correlated with advanced maternal age and abnormal ultrasound findings. In cases with terminal deletions, prenatal ultrasound plays a more important role for prenatal diagnosis., (Copyright © 2014. Published by Elsevier B.V.)

Objective: The purpose of this study is to investigate the potential genetic alterations at DNA level in patients with ovarian endometriosis by high-resolution array-based comparative genomic hybridization (array-CGH) analysis., Methods: Following the laparoscopic surgical and the post-operative pathological examination, genomic DNA was extracted from endometriomas of 11 women with endometriosis and endometrial tissue of the controls and analyzed by array-CGH. Real-time PCR was used for confirmation the result of array-CGH analysis and detected the DNA copy number variations of the eutopic endometrium from the five patients with the duplication in 20q13.33 region., Results: All 11 patients with ovarian endometriosis were diagnosed through the laparoscopic surgical and the post-operative pathological examination. We found occurrence of genomic duplication at 20q13.33 chromosomal region with gain of GATA5 and SLCO4A1 genes in 5 of 11 endometriomas from patients., Conclusion: The results of the present study suggest that there was 20q13.33 duplication in women with ovarian endometriosis. This effect might be due to the alterations of GATA5 and SLCO4A1 genes in the gain region, through involving the metabolism of the steroid hormone.

Background: Assisted reproductive technologies include in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). It has been shown that embryos derived from ART have higher rates of aneuploidy. Although the majority of ART pregnancies are genetically normal, it is suspected that aneuploid embryos may persist as mosaics and lead to confined placental mosaicism (CPM). Due to the greater risks of sperm aneuploidy in infertile men, CPM may be more prevalent in ICSI than IVF pregnancies. In this report, we investigated the prevalence of CPM in IVF and ICSI pregnancies using comparative genomic hybridization and flow cytometry., Methods: The placenta and umbilical cord blood were collected after birth. To determine the presence of CPM, karyotypes of umbilical cord blood were compared to the results of placental analyses. For each placenta, multiple villous sites were investigated for DNA gains/losses and polyploidy using comparative genomic hybridization and flow cytometry. Detected abnormalities were further confirmed by fluorescent in-situ hybridization (FISH)., Results: In total, 134 IVF/ICSI cases were investigated. CPM was detected in five of these cases (5/134) giving an overall rate of 3.73%. CPM was detected in one IVF case (1/31; 3.23%) and four ICSI cases (4/103; 3.88%). The prevalence of CPM in IVF and ICSI pregnancies was not statistically different from each other. CPM was not observed in 13 ICSI and 6 IVF cases that were determined to be small for gestational age (SGA)., Conclusions: The prevalence of CPM in ICSI pregnancies is not greater than IVF pregnancies. In addition, the overall prevalence of CPM in ART pregnancies (IVF and ICSI) is similar to that of the general population. CPM was not observed in the limited cases that were affected by small for gestational age. Our results suggest that ART pregnancies are not at a greater risk for CPM., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: Chronic infantile neurologic, cutaneous, articular (CINCA) syndrome, also known as neonatal-onset multisystem inflammatory disease (NOMID), is a dominantly inherited systemic autoinflammatory disease. Although heterozygous germline gain-of-function NLRP3 mutations are a known cause of this disease, conventional genetic analyses fail to detect disease-causing mutations in ∼40% of patients. Since somatic NLRP3 mosaicism has been detected in several mutation-negative NOMID/CINCA syndrome patients, we undertook this study to determine the precise contribution of somatic NLRP3 mosaicism to the etiology of NOMID/CINCA syndrome., Methods: An international case-control study was performed to detect somatic NLRP3 mosaicism in NOMID/CINCA syndrome patients who had shown no mutation during conventional sequencing. Subcloning and sequencing of NLRP3 was performed in these mutation-negative NOMID/CINCA syndrome patients and their healthy relatives. Clinical features were analyzed to identify potential genotype-phenotype associations., Results: Somatic NLRP3 mosaicism was identified in 18 of the 26 patients (69.2%). Estimates of the level of mosaicism ranged from 4.2% to 35.8% (mean ± SD 12.1 ± 7.9%). Mosaicism was not detected in any of the 19 healthy relatives (18 of 26 patients versus 0 of 19 relatives; P < 0.0001). In vitro functional assays indicated that the detected somatic NLRP3 mutations had disease-causing functional effects. No differences in NLRP3 mosaicism were detected between different cell lineages. Among nondescript clinical features, a lower incidence of mental retardation was noted in patients with somatic mosaicism. Genotype-matched comparison confirmed that patients with somatic NLRP3 mosaicism presented with milder neurologic symptoms., Conclusion: Somatic NLRP3 mutations were identified in 69.2% of patients with mutation-negative NOMID/CINCA syndrome. This indicates that somatic NLRP3 mosaicism is a major cause of NOMID/CINCA syndrome., (Copyright © 2011 by the American College of Rheumatology.)

Objective: To study the influence of types 2 and 3 confined placental mosaicism (CPM) on pregnancy outcome., Method: From 13 809 chorionic villus samplings (CVSs), karyotype after long-term cultured villi (LTC-villi) was systematically performed. Next, in case of suspicion of CPM, karyotype after short-term cultured villi (STC-villi) was established to define type 2 CPM (chromosomal abnormality limited to the mesenchymal core) or type 3 CPM (chromosomal abnormality found both in the cytotrophoblast and the mesenchymal core). Confirmatory amniocentesis was performed to exclude fetal mosaicism. Uniparental disomy (UPD) testing was carried out when the abnormal cell line involved chromosomes 5, 6, 7, 15 or 16., Results: Fifty-seven CPM cases were observed (57/13 809 = 0.41%) and of these, 37 were type 2 and 20 were type 3 CPM. Incidence of preterm infants, neonatal hypotrophy and adverse pregnancy outcome were comparable between patients in whom type 2 CPM was demonstrated and the control population. In contrast, for the type 3 CPM the incidence of these factors was higher than for the control population., Conclusion: When a CPM is suspected, it appears essential to determine type, since type 2 has no effect on fetal development and type 3 is associated with preterm infants, low birth weight and adverse pregnancy outcome., (Copyright © 2010 John Wiley & Sons, Ltd.)

Objective: To describe chromosomal abnormalities in spontaneous abortion material., Methods: A retrospective compilation of karyotype analysis of slides stained with Band G was carried out by optical microscopy with materials of 428 abortion products referred for study., Results: There were 145 normal results (33.9%) and 237 abnormal results (55.4%). In 46 samples there was no cell growth (10.7%). Numerical abnormalities were the most frequent, especially trisomy 16 (41 cases), triplodia (27 cases), monosomy X (26 cases), tetraploidy (13 cases) and trisomy 15 (13 cases)., Conclusion: Cytogenetic alterations are an important cause of pregnancy loss and their detection helps the genetic counseling to the couple. Trisomy 16 is the most often found change.

Objective: To define the prevalence of low-level sex chromosome mosaicism in a cohort of infertile men., Design: Prospective cohort study of infertile men., Setting: Tertiary university infertility center., Patient(s): One hundred one consecutive men who presented with primary infertility for evaluation., Intervention(s): Fluorescent in situ hybridization for X and Y was performed on 200 cells, and if an aberrant sex chromosome complement was noted, 400 cells were counted. For this study, any abnormality in sex chromosome complement was defined as micromosaicism., Main Outcome Measure(s): Low-level sex chromosome mosaicism., Result(s): Sixty-seven of these men (67%) had no mosaicism, and 34 men (34%) had micromosaicism. The median percentage of abnormal chromosomes in these men was 2%. The mean age of the men without micromosaicism was lower than for men with micromosaicism (31.1 years vs. 35.2 years). A trend toward higher FSH levels in men with low-level mosaicism was seen. Median sperm density and percent motility were higher in normal men. Percent normal morphology was identical between groups., Conclusion(s): We found low-level sex chromosome mosaicism in 34% of infertile men who presented for evaluation. Men with low-level mosaicism were significantly older. Low-level mosaicism may emerge with advancing age and may therefore help to explain the decline in fertility potential seen in older men., (Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate the effect of the improvement of chromosome analysis on the cytogenetic findings of Turner syndrome (TS) patients., Methods: Retrospective study of the results of the karyotypes of 260 patients with TS, regarding banding techniques, number of cells analyzed and results of investigation of Y-chromosome sequences. According to karyotype, divided in 45,X; sex chromosome mosaicism without Y; structural aberrations of sex chromosomes with or without mosaicism; sex chromosome mosaicism with Y., Results: 45,X was the most frequent karyotype (108), followed by structural aberrations (88) and mosaics (58 without Y and 6 with Y). Introduction of banding techniques and increase in the number of cells analyzed resulted in progressive decrease of 45,X karyotype and increase of structural aberrations. The study of Y-chromosome sequences was performed in 96 cases of which 10 resulted positive., Conclusions: Improvement of chromosome analysis over the years has modified the cytogenetic profile of TS.

Down syndrome (DS) is caused by trisomy of all or part of human chromosome 21 (HSA21) and is the most common genetic cause of significant intellectual disability. In addition to intellectual disability, many other health problems, such as congenital heart disease, Alzheimer's disease, leukemia, hypotonia, motor disorders, and various physical anomalies occur at an elevated frequency in people with DS. On the other hand, people with DS seem to be at a decreased risk of certain cancers and perhaps of atherosclerosis. There is wide variability in the phenotypes associated with DS. Although ultimately the phenotypes of DS must be due to trisomy of HSA21, the genetic mechanisms by which the phenotypes arise are not understood. The recent recognition that there are many genetically active elements that do not encode proteins makes the situation more complex. Additional complexity may exist due to possible epigenetic changes that may act differently in DS. Numerous mouse models with features reminiscent of those seen in individuals with DS have been produced and studied in some depth, and these have added considerable insight into possible genetic mechanisms behind some of the phenotypes. These mouse models allow experimental approaches, including attempts at therapy, that are not possible in humans. Progress in understanding the genetic mechanisms by which trisomy of HSA21 leads to DS is the subject of this review.

Objective: To determine if mosaicism that occurs in infertility and assisted reproductive technologies continues in the late first trimester and if this is unique to infertility or occurs in all pregnancies., Design: Retrospective case-controlled study., Setting: University hospital., Patient(s): 5337 consecutive chorionic villus samplings (CVS)., Intervention(s): None., Main Outcome Measure(s): Mosaic karyotypes at CVS., Result(s): We confirmed 69 mosaic karyotypes, a rate of 1.29%. Comparing spontaneous pregnancies with pregnancies from infertility treatment, no difference was found in the prevalence of mosaicism: 1.22% versus 1.32%, respectively. Subgroup analysis of infertile couples, comparing in vitro (assisted reproduction) with in vivo fertilization (other treatments) revealed a mosaicism rate of 1.84% and 0.41%, respectively. Confined placental mosaic (CPM) rates for infertility treated pregnancies and spontaneously conceived pregnancies were 0.88% and 0.92%, respectively. Subgroup analysis of infertile patients revealed a CPM rate of 1.15% for in vitro fertilization treatment and 0.41% for in vivo fertilization treatment. These results were not statistically significant., Conclusion(s): There was no difference in the prevalence of mosaicism at the end of the first trimester in pregnancies conceived spontaneously compared with those with infertility. There was no difference in the prevalence of mosaicism when in vitro and in vivo treatment were compared.

Recently it has been suggested that the human brain contains aneuploid cells; however the nature and magnitude of neural aneuploidy in health and disease remain obscure. Here, we have monitored aneuploidy in the cerebral cortex of the normal, Alzheimer's disease (AD) and ataxia telangiectasia (AT) brain by molecular cytogenetic approaches scoring more than 480,000 neural cells. Using arbitrarily selected set of DNA probes for chromosomes 1, 7, 11, 13, 14, 17, 18, 21, X and Y we have determined the mean rate of stochastic aneuploidy per chromosome as 0.5% in the normal human brain (95%CI 0.2-0.7%; SD 0.2%). The overall proportion of aneuploid cells in the normal brain has been estimated at approximately 10%. In the AT brain, we observed a 2-to-5 fold increase of stochastic aneuploidy randomly affecting different chromosomes (mean 2.1%; 95%CI - 1.5-2.6%; SD 0.8%). The overall proportion of aneuploid cells in the brain of AT individuals was estimated at approximately 20-50%. Compared with sex- and age-matched controls, the level of stochastic aneuploidy in the AD brain was not significantly increased. However, a dramatic 10-fold increase of chromosome 21-specific aneuploidy (both hypoploidy and hyperploidy) was detected in the AD cerebral cortex (6-15% versus 0.8-1.8% in control). We conclude that somatic mosaic aneuploidy differentially contributes to intercellular genomic variation in the normal, AD and AT brain. Neural aneuploidy leading to altered cellular physiology may significantly contribute to the pathogenesis of neurodegenerative diseases. These data indicate neural aneuploidy to be a newly identified feature of neurodegenerative diseases, similar to other devastative disorders hallmarked by aneuploidy such as chromosome syndromes and cancer.

Background & Objective: Chromosome aneuploidy plays an important role in infertility, early pregnancy wastage and perinatal mortality. Cytogenetic & fluorescent in situ hybridization (FISH) studies on developmentally arrested and morphologically poor embryo have shown high frequency of chromosomal abnormality and mosaicism. In this study, we attempted to evaluate chromosome aneuploidy and mosaicism on human embryos through the use of FISH., Methods: Sixty one grade IV un-transferable embryos were obtained from 25 patients undergoing in vitro fertilization (IVF). Forty six embryos were studied by FISH; 15 were lost during transport and handling. FISH probes (non-commercial) for centromeres of chromosome X, Y, 1 and 18 were used for the study. Zona of embryos were dissolved in 0.01N HCl containing 0.1 per cent Tween 20 for 2-3 min., Results: Interpretable FISH results were obtained in 24 embryos. Nineteen embryos (79.2%) were disomic (normal) for chromosome X/Y or 1/18 and five (20.8%) were abnormal. Among five abnormal embryos two were triploidy (from same patient), one was double mosaic aneuploidy, one was mosaic aneuploidy and one was trisomy for sex chromosome (XXY). There was eleven embryos with presence of Y chromosome i.e., male and three embryos were female., Interpretation & Conclusion: Skewing of sex ratio (11M vs. 3F) and low chromosome aneuploidy were observed in this preliminary study, however, it will be premature to conclude as the numbers of embryos studied were limited and so were the numbers of FISH probes used.

In the present study, 73 cases with a clinical diagnosis of Turner syndrome, or with primary or secondary amenorrhoea without frank Turner phenotype, were evaluated for presence of low level Y chromosome mosaicism using molecular methods. Fluorescence in-situ hybridization for centromere and q arm of the Y chromosome and nested polymerase chain reaction for the sex determining region on Y (SRY) gene were performed in peripheral blood, buccal cells and gonadal biopsies. The overall frequency of Y chromosome mosaicism was found to be 18% (13/73 cases). Four cases (16%) of Turner syndrome had Y chromosome mosaicism, seven cases (28%) with primary amenorrhoea and two cases (9%) with secondary amenorrhoea had Y chromosome mosaicism. Histologically detectable gonadoblastoma was observed in one of seven cases (14%) that had Y chromosome mosaicism. This frequency is lower than that reported previously, underscoring the need for large prospective investigations to determine the frequency of Y chromosome mosaicism and occurrence of gonadoblastoma in cases of Turner syndrome and other forms of amenorrhoea.

Purpose: To investigate the genetic background of familial severe myoclonic epilepsy in infancy (SMEI) cases., Methods: We performed mutation analyses of the sodium-channel gene SCN1A in two Japanese brothers with clinical features of SMEI and their parents, who had no history of febrile and epileptic seizures., Results: Each patient showed nucleotide changes (c.[730G>T; 735G>T; 736A>T]) in the coding exon 6 of SCN1A that led to a truncation of the channel protein. Their father showed no mutations, but their mother showed the same mutation in a subpopulation of lymphocytes., Conclusions: The maternal mosaicism explains the identical SCN1A mutations in the two brothers. This highlights the importance of investigating parental mosaicism even in sporadic SMEI cases.

Objectives: To produce a fully searchable Microsoft Access database of mosaic and non-mosaic cytogenetic abnormalities, detected during diagnostic chorionic villi sampling (CVS) to aid laboratories in predicting pregnancy outcome, in particular differentiating between cases of likely genuine fetal cytogenetic abnormalities and those likely to represent confined placental mosaicism (CPM)., Methods: Retrospective collection of referral data, initial karyotype data, follow-up karyotype data and pregnancy outcome data from almost all cytogenetically abnormal diagnostic CVS, processed in UK National Health Service laboratories, between 1987 and 2000. Collection of similar data from a published series of CVS and individual case reports., Results: A fully searchable database of abnormal CVS cases, containing over 5000 entries, has been produced. This is available to download at http://www.ncl.ac.uk/cvs/., Conclusions: Following detection of a cytogenetic abnormality during prenatal diagnosis using CVS, use of this database allows rapid access to comparable cases from the United Kingdom and the literature. This database will improve the speed of availability and quality of information available to clinicians and patients for pregnancy management and counselling purposes. The database has been designed with future data collection in mind, and can be developed for wider research use, through more detailed registries of individual chromosome abnormalities., (Copyright (c) 2006 John Wiley & Sons, Ltd.)

During 1992-2001, 673 Down syndrome patients were referred to the Department of Human Genetics in Alexandria. Regular (free) trisomy 21 constituted 95.4% of cases; Robertsonian translocation 2.7%; and mosaicism 0.7%. In 8 cases, regular trisomy 21 was associated with structural or numerical chromosome anomalies. Translocation was parentally inherited for 33.3% of cases and maternal transmission was twice as common as paternal. Two translocated Down syndrome fetuses were diagnosed prenatally in a t(14;21) carrier mother. Mean maternal age was high in regular trisomy 21 (38.2 years) but not in translocation (25.3 years). There was an excess of males in all groups except the mosaic group where the male:female ratio was 0.67. Cytogenetic investigations assist in patient management and family counselling.