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The expedience of using oocytes with morphological dysmorphism in assisted reproduction tech- nology programs is debatable. This study aimed to estimate morphological and molecular cytogenetic char- acteristics of enlarged oocytes and to predict results of their further fertilization. Among 774 oocytes retrieved from 80 patients, 83 (11%) cells were enlarged. Morphometric analysis showed the diameter of the ooplasm to be (176.67 ± 1.76) μm and the diameter with ZP (200.8 ± 4.24) μm. Among these giant oocytes, 47 (56.6%) were at the metaphase II stage, 26 (31.3%) at the metaphase I stage, and 10 (12.1%) at the prophase I stage. The retrieved giant oocytes were characterized by dysmorphism of endo- and exocytoplasmic structures. Among 47 cells at the metaphase II stage, 40 (85.1%) oocytes had two polar bodies, three (6.4%) oocytes had one polar body, and four (8.5%) oocytes had a fragmented polar body. The assessment of the presence of mei- otic spindle by polarization microscopy showed that 39 (83%) oocytes had two meiotic spindles, 3 (6.4%) oocytes had one meiotic spindle, and 5 oocytes (10.6%) had no visualized meiotic spindles despite the pres- ence of polar bodies. After fertilization of 47 oocytes at the metaphase II stage, pronuclei were detected in 42 (89.4%) cells, including 9 (21.4%) oocytes with two pronuclei, 27 (63.3%) oocytes with 3 pronuclei, and 6 (15.3%) oocytes with four pronuclei. The molecular cytogenetic analysis demonstrated that the embryos obtained after fertilization of giant oocytes had a polyploid chromosome set number. Thus, the results of our study showed the inexpediency of using giant oocytes for further fertilization.

Развитие современной биологии и медицинской генетики остро ставит вопрос философской интерпретации результатов тестирования на генетическую предрасположенность. Медицинские и юридические последствия полученной информации и ее использование в клинической практике не до конца изучены, нормативное правовые акты, регламентирующие процесс обследования на генетические маркеры заболеваний не совершенны. При этом генетическое тестирование является наиболее перспективным направлением современной медицинской науки и здравоохранения. В статье изложены взгляды автора на эти проблемы., The development of modern biology and medical genetics raises the question of the philosophical interpretation of the results of testing for genetic susceptibility. The medical and legal implications of the information obtained and its use in clinical practice have not been fully studied, normative legal acts regulating the examination process for genetic markers of diseases are not perfect. At the same time, genetic testing is the most promising area of ​​modern medical science and health care. The article sets out the views of the author on these problems., №13(168) (2019)

Sex chromosome abnormalities are the most common chromosomal abnormalities detected on prenatal diagnosis and at birth with an estimated incidence of 1 in 448 newborns. The clinical severity of sex chromosome anomalies vary according to related aneuploidies and mosaic status and it is less than that associated with autosomal aneuploidy. Disorders of sex development (DSDs) are congenital conditions in which development of the chromosomal, gonadal, or anatomic sex is atypical and may affect up to 1:1000 individuals in the population. The Genital phenotype has a very wide spectrum and in many cases the genotype-phenotype association is weak and it is difficult to distinguish pathologies with clear limits. In this groups Phenotypic findings are analyzed in relation to cytogenetic and molecular cytogenetics in order to determine etiology. In our study different clinical Characteristics of sexual development were investigated in order to evaluate the cytogenetic and molecular cytogenetic data in patient's peripheral blood, in Eskisehir Osmangazi University Faculty of Medicine Medical Genetics Department. Chromosome aberration frequency was evaluated in 469 cases that were referred with various clinical suspicions of sex chromosomal abnormalities, including Klinefelter Syndrome, Hypogonadotropic Hypogonadism, Ambigus Genitalia, Azoospermia, Turner Syndrome, Primary Amenorrhea and Primary İnfertility. Karyotype results of the 469 patients revealed %87 with normal chromosome composition (n=408) and %13 with chromosomal abnormalities (n=61). Autosomal abnormalities were detected in 8 cases with a frequency of %13.11, whereas sex chromosome anomalies were identified in 53 cases with a frequency of 86.89%. In autosomal abnormalities the most commonly detected abnormalities were translocations and in sex chromosome abnormalities it was XXY. In sex chromosome abnormalities, the most commonly detected abnormality was in cases with Klinefelter Syndrome (50%). Followed by Hypogonadotropic Hypogonadism (27.27%), Ambiguous Genitale (21.43%), Azoospermia (14.2%), Turner Syndrome (12.33%), Primary Amenorrhea (7.4%) and Primary İnfertility (5.13). In conclusion, retrospective evaluation of cytogenetic and molecular cytogenetic analysis of the referral cases over 3 years contributes to formation of regional data. Cinsiyet kromozomlarının anomalileri prenatal ve postnatal tanıda en sık gözlenen kromozom anomalileridir ve insidansı 448 yenidoğanda birdir. Cinsiyet kromozom anomalili bireylerdeki klinik, ilgili anöploidiler ve mozaiklik durumuna göre değişkenlik gösterir ve otozomal anöploidilere göre daha hafif klinik göstermektedir.Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozukluk Cinsiyet gelişme bozuklukları (CGB), kromozomal gonodal veya anotomik cinsiyet gelişiminin atipik olduğu konjenital durumlardır. Retrospektif çalışmamıza dahil edilen 469 olguda, %87 (n=408) normal kromozom kuruluşu ve %13 (n=61) kromozomal anomaliler tespit edilmiştir. Toplam 61 anomalili olgunun %13.11'i (n=8) otozomal anomaliler, %86.89'u (n=53) cinsiyet kromozom anomalilerinden oluşmaktadır. Karyotipleme sonucunda, otozomal anomalilerde en çok translokasyon tipi anomaliler (n=5), cinsiyet kromozom anomalilerinde ise en çok 47,XXY (n=33) kromozom kuruluşu tespit edilmiştir. Periferik kandan elde edilen karyotip analizinde en çok Klinefelter Sendromu olgularında anomali tespit edilmiştir (%50). Takiben Hipogonadotropik Hipogonadism (%27.27), Ambigus Genitalya (%21.43), Azoospermi (%14.2), Turner Sendromu (%12.33), Primer Amenore (%7.4) ve Primer İnfertilite (%5.13) olgularında kromozomal anomaliler gözlenmiştir.

Human testicular germ cell tumours (TGCTs) of adolescents and adults, both seminomas and non-seminomas, originate from intratubular germ cell neoplasia (IGCN). Comparative genomic hybridization (CGH) was applied to microdissected samples from different stages of the development of a seminoma and a mixed non-seminoma, including IGCN of both. The different stages of the seminoma development, namely IGCN, intratubular and invasive seminoma, showed a very similar pattern of chromosomal imbalances, including gains of parts of 7, 8,12,14, and X, and losses of parts of 3, 4, 5, 10, 11, 12q, 16, 18, 22, and Y. A more heterogeneous pattern was found for the non-seminoma. Some aberrations were present only in IGCN, or in IGCN and in all invasive components (gains of parts of 1q, 17, 19p, 20q, and 22, and losses of parts of 4, 5, 9p, 13, and 18q), while others were present in a less consistent pattern. These are the first reported CGH data from different stages in the development of TGCTs. Although only two cases were studied, the results suggest that particular numerical changes of (parts of) chromosomes are involved in the early development and progression of this cancer. Copyright (C) 2000 John Wiley & Sons, Ltd.

Cytogenetically, testicular germ cell tumors of adolescents and adults (TGCTs) are characterized by gain of 12p-sequences, most often through isochromosome formation (i(12p)), Fluorescence in situ hybridization (FISH) has shown that i(12p))-negative TGCTs also cryptically contain extra 12p-sequences. The consistency of 12p-over-representation in all histological subtypes of TGCTs, including their preinvasive stage, suggests that gain of one or more genes on 12p is crucial in the development of this cancer. So far, studies aimed at the identification of the relevant gene(s) were based on the 'candidate-gene approach'. No convincing evidence in favor of or against a particular gene has been reported. We combined conventional karyotyping, comparative genomic hybridization, and FISH to identify TGCTs with amplifications of restricted regions of 12p, Out of 49 primary TGCTs (23 without i(12p), 13 with and 13 unknown), eight tumors (six without i(12p) and two unknown) showed amplifications corresponding to 12p11.1-p12.1. Using bicolour-FISH, physical mapping, and semi-quantitative polymerase chain reactions, the size of the shortest region of overlap of amplification (SROA) was estimated to be between 1750-3000 kb, In addition, we mapped a number of genes in and around this region. While fourteen known genes could be excluded as candidates based on their location outside this region, we demonstrate that KRAS2, JAW1 and SOX5 genes are localized within the SROA, While KRAS2 and JAW1 map to the proximal border of the SROA, SOX5 maps centrally in the SROA, KRAS2 and JAW1 are expressed in all TGCTs, whereas one 12p amplicon-positive TGCT lacks expression of SOX5, The critical region of 12p over-represented in TGCTs is less than 8% of the total length of the short arm of chromosome 12, It will be helpful in the identification of the gene(s) involved in TGCT-development.

Cytogenetically, testicular germ cell tumors of adolescents and adults (TGCTs) are characterized by gain of 12p-sequences, most often through isochromosome formation (i(12p)), Fluorescence in situ hybridization (FISH) has shown that i(12p))-negative TGCTs also cryptically contain extra 12p-sequences. The consistency of 12p-over-representation in all histological subtypes of TGCTs, including their preinvasive stage, suggests that gain of one or more genes on 12p is crucial in the development of this cancer. So far, studies aimed at the identification of the relevant gene(s) were based on the 'candidate-gene approach'. No convincing evidence in favor of or against a particular gene has been reported. We combined conventional karyotyping, comparative genomic hybridization, and FISH to identify TGCTs with amplifications of restricted regions of 12p, Out of 49 primary TGCTs (23 without i(12p), 13 with and 13 unknown), eight tumors (six without i(12p) and two unknown) showed amplifications corresponding to 12p11.1-p12.1. Using bicolour-FISH, physical mapping, and semi-quantitative polymerase chain reactions, the size of the shortest region of overlap of amplification (SROA) was estimated to be between 1750-3000 kb, In addition, we mapped a number of genes in and around this region. While fourteen known genes could be excluded as candidates based on their location outside this region, we demonstrate that KRAS2, JAW1 and SOX5 genes are localized within the SROA, While KRAS2 and JAW1 map to the proximal border of the SROA, SOX5 maps centrally in the SROA, KRAS2 and JAW1 are expressed in all TGCTs, whereas one 12p amplicon-positive TGCT lacks expression of SOX5, The critical region of 12p over-represented in TGCTs is less than 8% of the total length of the short arm of chromosome 12, It will be helpful in the identification of the gene(s) involved in TGCT-development.

Overrepresentation of the short arm of chromosome 12 is frequently detected in human testicular germ cell tumors of adolescents and adults (TGCT). This overrepresentation mostly results from the formation of an isochromosome: i(12p). Whether the overrepresentation consistently involves the complete 12p arm including the centromere is still unclear. We studied five TGCT-derived cell lines (NT2, 2102Ep, H12.1, NCCIT, and S2), combining conventional chromosome banding, fluorescence in situ hybridization (FISH), and comparative genomic hybridization (CGH) to investigate the suitability of each of these techniques to detect aberrations involving chromosome 12. Karyotyping showed one or more i(12p)s in NT2, 2102Ep, H12.1, and S2. However, FISH with a centromere-specific probe (p alpha 12J8), a 12p ''paint'' and a 12p11.2-12.1 region-specific probe yeast artificial chromosome (YAG)#5 and CGH could not confirm the presence of an i(12p) in S2. Additional randomly distributed 12p sequences were detected by FISH in H12.1, NCCIT, and S2. In most of these cases, (a part of) of the centromere was included. All overrepresented 12p regions, except for those in S2, showed hybridization with YAC#5. CGH showed increased copy numbers of the complete 12p arm in the cell lines with one or more i(12p)s but no overrepresentation was noted in the cell lines without i(12p). In metaphase spreads, the centromeric block of the i(12p)s differed in size as compared with those of normal chromosomes 12. This was rarely noted in interphase nuclei. A decrease in size of the centromeric block in 2102Ep and H12.1 caused a weak FISH signal, which was difficult to detect, especially in interphase nuclei. The ratio between p alpha 12H8- and YAC#5-derived signals reflected the presence or absence of one or more i(12p)s. Our results indicate that double FISH with a centromere- and a 12p-specific probe can be used to detect 12p ovrrepresentation [including i(12p)] in TGCT both in metaphase spreads and interphase nuclei. CGH confirmed the relative overrepresentation of 12p sequences as detected by FISH and showed that in these cell lines the complete 12p was involved.

KG-1 and its less differentiated subline KG-1a are leukemia cell lines used in research in a number of laboratories. The karyotypes of the two lines were initially identical. In the following years, further analysis revealed that the cell lines had acquired additional karyotypical abnormalities and differed in the presence of certain typical chromosomal rearrangements. To obtain cytogenetic authentication prior to the use of the two cell lines, we analyzed their karyotype by combining DAPI- and CMA-chromosome bandings and a fluorescence in situ hybridization (FISH)-based approach by using BAC clones useful for the identification of chromosome regions of interest. Sequences of the MYC, PLZF, RARA and BCR genes, that are known to play a critical role in leukemogenesis, and certain BAC clones mapped to five known common fragile sites (CFS) were used for the FISH analysis. A telomeric probe (TTAGGG)n and a set of BAC clones were used to characterize the marker chromosome der(1) that was observed in the cell line KG-1a. The existence of notable differences between the karyotype of the KG-1a cell line previously described, and that described in this study, demonstrate that the use of established cancer cell lines should be preceded by cytogenetic and/or molecular characterization.

Breeding programs aiming at transferring desirable genes from one species to another through interspecific hybridization and backcrossings often produce monosomic and disomic additions as intermediate crossing products. Such aneuploids contain alien chromosomes added to the complements of the recipient parent and can be used for further introgression programs, but lack of homoeologous recombination and inevitable segregation of the alien chromosome at meiosis make them often less ideal for producing stable introgression lines. Monosomic and disomic additions can have specific morphological characteristics, but more often they need additional confirmation of molecular marker analyses and assessment by fluorescence in situ hybridization with genomic and chromosome-specific DNA as probes. Their specific genetic and cytogenetic properties make them powerful tools for fundamental research elucidating regulation of homoeologous recombination, distribution of chromosome-specific markers and repetitive DNA sequences, and regulation of heterologous gene expression. In this overview we present the major characteristics of such interspecific aneuploids highlighting their advantages and drawbacks for breeding and fundamental research.

Human testicular germ cell tumours (TGCTs) of adolescents and adults, both seminomas and non-seminomas, originate from intratubular germ cell neoplasia (IGCN). Comparative genomic hybridization (CGH) was applied to microdissected samples from different stages of the development of a seminoma and a mixed non-seminoma, including IGCN of both. The different stages of the seminoma development, namely IGCN, intratubular and invasive seminoma, showed a very similar pattern of chromosomal imbalances, including gains of parts of 7, 8,12,14, and X, and losses of parts of 3, 4, 5, 10, 11, 12q, 16, 18, 22, and Y. A more heterogeneous pattern was found for the non-seminoma. Some aberrations were present only in IGCN, or in IGCN and in all invasive components (gains of parts of 1q, 17, 19p, 20q, and 22, and losses of parts of 4, 5, 9p, 13, and 18q), while others were present in a less consistent pattern. These are the first reported CGH data from different stages in the development of TGCTs. Although only two cases were studied, the results suggest that particular numerical changes of (parts of) chromosomes are involved in the early development and progression of this cancer. Copyright (C) 2000 John Wiley & Sons, Ltd.

Overrepresentation of the short arm of chromosome 12 is frequently detected in human testicular germ cell tumors of adolescents and adults (TGCT). This overrepresentation mostly results from the formation of an isochromosome: i(12p). Whether the overrepresentation consistently involves the complete 12p arm including the centromere is still unclear. We studied five TGCT-derived cell lines (NT2, 2102Ep, H12.1, NCCIT, and S2), combining conventional chromosome banding, fluorescence in situ hybridization (FISH), and comparative genomic hybridization (CGH) to investigate the suitability of each of these techniques to detect aberrations involving chromosome 12. Karyotyping showed one or more i(12p)s in NT2, 2102Ep, H12.1, and S2. However, FISH with a centromere-specific probe (p alpha 12J8), a 12p ''paint'' and a 12p11.2-12.1 region-specific probe yeast artificial chromosome (YAG)#5 and CGH could not confirm the presence of an i(12p) in S2. Additional randomly distributed 12p sequences were detected by FISH in H12.1, NCCIT, and S2. In most of these cases, (a part of) of the centromere was included. All overrepresented 12p regions, except for those in S2, showed hybridization with YAC#5. CGH showed increased copy numbers of the complete 12p arm in the cell lines with one or more i(12p)s but no overrepresentation was noted in the cell lines without i(12p). In metaphase spreads, the centromeric block of the i(12p)s differed in size as compared with those of normal chromosomes 12. This was rarely noted in interphase nuclei. A decrease in size of the centromeric block in 2102Ep and H12.1 caused a weak FISH signal, which was difficult to detect, especially in interphase nuclei. The ratio between p alpha 12H8- and YAC#5-derived signals reflected the presence or absence of one or more i(12p)s. Our results indicate that double FISH with a centromere- and a 12p-specific probe can be used to detect 12p ovrrepresentation [including i(12p)] in TGCT both in metaphase spreads and interphase nuclei. CGH confirmed the relative overrepresentation of 12p sequences as detected by FISH and showed that in these cell lines the complete 12p was involved.

XX maleness is the most common condition in which testes develop in the absence of a cytogenetically detectable Y chromosome. Using molecular techniques, it is possible to detect Yp sequences in the majority of XX males. In this study, we could detect Y-specific sequences, including the sex-determining region of the Y chromosome (SRY), using fluorescence in situ hybridization. In 5 out of 6 previously unpublished XX males, SRY was translocated onto the terminal part of an X chromosome. This is the first report in which translocation of an SRY-bearing fragment to an X chromosome in XX males could be directly demonstrated.