Complex cytogenetic and molecular-genetic analysis of males with spermatogenesis failure

The chromosomal anomalies, microdeletions of AZF region of Y-chromosome and CFTR gene mutations have been studied among 80 infertile men with idiopathic spermatogenetic failure: 36 (45 %) patients with aspermia, 19 (24 %) patients with azoospermia and 25 (31 %) patients with severe oligoasthenoteratozoospermia. In total 30 % males with spermatogenetic failure genetic factor of infertility was observed. Karyotype anomalies were observed in 17.5 % of infertile men, within 16.2 % numerical and structural gonosomal anomalies and in 1.3 % – Robertsonian translocation were revealed. In 11 % males with spermatogenetic failure, Y-chromosome AZF region microdeletions were detected. The frequency of CFTR major mutation F508del among infertile men was 6.25 %. 5T allele of polymorphic locus IVS8polyT was detected in 7.5 % of examined men. The results obtained indicate the high complexity of cytogenetic and moleculargenetic studies of male infertility.Изучали аномалии хромосом, микроделеции AZF региона Y-хромосомы и мутации гена ТРБМ у 80 мужчин с идиопатическими нарушениями сперматогенеза, а именно: у 36 (45 %) пациентов с аспермией, 19 (24 %) пациентов с азооспермией и 25 (31 %) пациентов с олигоастенотератозооспермией IV степени. В общем у 30 % мужчин с нарушениями сперматогенеза установлены генетические факторы бесплодия. Нарушения кариотипа наблюдали у 17.5 % бесплодных мужчин, среди них у 16.2 % – количественные и структурные аномалии хромосом и у 1.3 % – робертсоновскую транслокацию. У 11 % мужчин с нарушениями сперматогенеза выявили микроделеции AZF региона Y хромосомы. Частота мажорной мутации F508del гена ТРБМ среди бесплодных мужчин составила 6.25 %. 5T аллель полиморфного локуса IVS8polyT выявили у 7.5 % обследованных мужчин. Полученные результаты свидетельствуют о высокой информативности комплексного цитогенетического и молекулярно-генетического исследования при мужском бесплодии

Cytogenetic and molecular analyses of de novo translocation dic(9;13)(p11.2;p12) in an infertile male

BACKGROUND: Whole arm t(9;13)(p11;p12) translocations are rare and have been described only a few times; all of the previously reported cases were familial. RESULTS: We present here an infertile male carrier with a whole-arm reciprocal translocation dic(9;13)(p11.2;p12) revealed by GTG-, C-, and NOR-banding karyotypes with no mature sperm cells in his ejaculate. FISH and genome-wide 400 K CGH microarray (Agilent) analyses demonstrated a balanced chromosome complement and further characterised the abnormality as a dicentric chromosome (9;13): dic(9;13)(pter→p11.2::p12→qter),neo(9)(pter→p12→neo→p11.2). An analysis of the patient’s ejaculated cells identified immature germ cells at different phases of spermatogenesis but no mature spermatozoa. Most (82.5%) of the germ cells were recognised as spermatocytes at stage I, and the cell nuclei were most frequently found in pachytene I (41.8%). We have also undertaken FISH analysis and documented an increased rate of aneuploidy of chromosomes 15, 18, X and Y in the peripheral blood leukocytes of our patient. To study the aneuploidy risk in leukocytes, we have additionally included 9 patients with non-obstructive azoospermia with normal karyotypes. CONCLUSIONS: We propose that the azoospermia observed in the patient with the dic(9;13)(p11.2;p12) translocation was most likely a consequence of a very high proportion (90%) of association between XY bivalents and quadrivalent formations in prophase I

Contribution of chromosomal abnormalities and genes of the major histocompatibility complex to early pregnancy losses

Aim. The determination of chromosomal abnormalities in samples from early pregnancy losses and allelic polymorphism of HLA–DRB1 and DQA1 genes in couples with recurrent miscarriage. Methods. Banding cytogenetic and interphase mFISH analysis, DNA extraction by salting method, PCR, agarose gel electrophoresis. Results. Cytogenetic and molecular-cytogenetic investigations of SA material identified karyotype anomalies in 32.4 % of cases with prevalence of autosomal trisomy – 42.65 %, triploidy – 30.38 % and monosomy X – 19.11 %. Complex analysis of frequency and distribution of allelic variants of genes HLA-DRB1 and HLA-DQA1 allowed establishing the alleles DRB1*0301, DRB1*1101-1104 and DQA1*0501 to be aggressor alleles in women with recurrent pregnancy loss (RPL). The cumulative homology of allelic polymorphism of more than 50 % of HLA-DRB1 and HLA-DQA1 loci between partners increases the risk of RPL by almost four times. Conclusion. The detected chromosome aneuploidies in the samples from products of conception and the changes in the major histocompatibility complex genes can cause the failure of a couples reproductive function and can lead to an early fetal loss.Мета. Встановити хромосомні аномалії у матеріалі ранніх репродуктивних втрат і алельний поліморфізм генів HLA – DRB1 і DQA1 у подружніх пар із навиковим невиношуванням вагітності. Методи. Стандартний цитогенетичний та інтерфазний mFISH методи, виділення ДНК методом висолювання, ПЛР, електрофорез в агарозному гелі. Результати. Цитогенетичні та молеку­лярно-цитогенетичні дослідженя матеріалу втрачених вагітностей показали аномалії каріотипу в 32.4 % випадках з переважанням аутосомних трисомій – 42.65 %, триплоїдій – 30.38 % і моносомії X – 19.11 %. Комплексний аналіз частоти і розподілу алельних варіантів генів HLA-DRB1 і HLA-DQA1 дозволив встановити, що DRB1*0301, DRB1*1101-1104 і DQA1*0501 є алелями-агресорами у жінок із ранніми репродуктивними втратами (РРВ). Сукупна гомологія алельного поліморфізму локусів HLA-DRB1 і HLA-DQA1 більше 50 % між партнерами збільшує ризик РРВ майже в чотири рази. Висновки. Встановлені хромосомні анеуплоїдії в матеріалі втрачених вагітностей та зміни в генах головного комплекса гістосумістності у подружніх пар можуть викликати порушення репродуктивної функції та ранню елімінацію плода.Цель. изучить хромосомные аномалии в биологическом материале ранних репродуктивных потерь и аллельный полиморфизм генов HLA – DRB1 и DQA1 у супружеских пар с привычным невынашиванием беременности. Методы. стан­дартный цитогенетический и интерфазный mFISH методы, выделение ДНК методом высаливания, ПЦР, электрофорез в агарозном геле. Результаты. Проведенные цитогенетические и молекулярно-цитогенетические исследований материала ранних репродуктивных потерь показали аномалии кариотипа в 32.4 % случаев с преобла­данием аутосомных трисомий – 42.65 %, триплоидий – 30.38 % и моносомии Х – 19.11 %. Комплексный анализ частоты и распределения аллельных вариантов генов HLA-DRB1 и HLA-DQA1показал, что DRB1*0301, DRB1*1101-1104 и DQA1*0501 являются аллелями-агрессорами у женщин с ранними репродуктивными потерями (РРП). Совокупная гомология аллельного полиморфизма локусов HLA-DRB1 и HLA-DQA1 более 50 % между партнерами увеличивает риск РРП почти в четыре раза. Выводы. Выявленные хромосомные анеуплоидии в материале самопроизвольных выкидышей и изменения в генах главного комплекса гистосовместимости у супружеских пар могут вызывать нарушения репродуктивной функции и элиминацию плода в раннем периоде беременности

INHERITED 15Q DUPLICATION IN THREE NOT RELATED UKRAINIAN FAMILIES

Background. 15q duplication syndrome (Dup15q) is caused by the presence of an extra maternally derived copy of the Prader-Willi/Angelman critical region (PWACR) within chromosome 15q11.2-q13.1. The syndrome is clinically identifiable and characterized by intellectual disability, hypotonia, motor delays, autism spectrum disorder, epilepsy, and behavioral difficulties [1, 12]. The prevalence of Dup15q in the general population is unknown but may be as high as 1:5000 [10]. The syndrome most commonly occurs in one of two forms: an extra isodicentric 15 chromosome or an interstitial duplication [4]. Most reported cases concern de novo mutation. Aim. To highlight the importance of genetic testing in patients with neurodevelopmental disorders and emphasizes the need for further research to understand the underlying genetic mechanisms of Dup15q depending on the origin of the inherited duplication. Materials and methods. The study used next-generation sequencing (NGS), multiplex ligation-dependent probe amplification (MLPA), and karyotype analysis to confirm the interstitial duplication. Results. We present the phenotype description and diagnostic prospects of three patients from different families who inherited interstitial 15q duplication from a phenotypically healthy mother. The patients exhibited symptoms consistent with Dup15q, including intellectual disability, delayed speech, difficulty understanding spoken language, hyperactivity, epilepsy and sleep disorders. Conclusion. The inherited interstitial duplication 15q is phenotypical presented only in case of maternal origin and vary in clinical presentation. We suggest as the first choice MLPA method as most cost and time effective in cases of Dup15q suspicion

Familial Infertility (Azoospermia and Cryptozoospermia) in Two Brothers—Carriers of t(1;7) Complex Chromosomal Rearrangement (CCR): Molecular Cytogenetic Analysis

Structural aberrations involving more than two breakpoints on two or more chromosomes are known as complex chromosomal rearrangements (CCRs). They can reduce fertility through gametogenesis arrest developed due to disrupted chromosomal pairing in the pachytene stage. We present a familial case of two infertile brothers (with azoospermia and cryptozoospermia) and their mother, carriers of an exceptional type of CCR involving chromosomes 1 and 7 and three breakpoints. The aim was to identify whether meiotic disruption was caused by CCR and/or genomic mutations. Additionally, we performed a literature survey for male CCR carriers with reproductive failures. The characterization of the CCR chromosomes and potential genomic aberrations was performed using: G-banding using trypsin and Giemsa staining (GTG banding), fluorescent in situ hybridization (FISH) (including multicolor FISH (mFISH) and bacterial artificial chromosome (BAC)-FISH), and genome-wide array comparative genomic hybridization (aCGH). The CCR description was established as: der(1)(1qter->1q42.3::1p21->1q42.3::7p14.3->7pter), der(7)(1pter->1p2 1::7p14.3->7qter). aCGH revealed three rare genes variants: ASMT, GARNL3, and SESTD1, which were ruled out due to unlikely biological functions. The aCGH analysis of three breakpoint CCR regions did not reveal copy number variations (CNVs) with biologically plausible genes. Synaptonemal complex evaluation (brother-1; spermatocytes II/oligobiopsy; the silver staining technique) showed incomplete conjugation of the chromosomes. Associations between CCR and the sex chromosomes (by FISH) were not found. A meiotic segregation pattern (brother-2; ejaculated spermatozoa; FISH) revealed 29.21% genetically normal/balanced spermatozoa. The aCGH analysis could not detect smaller intergenic CNVs of few kb or smaller (indels of single exons or few nucleotides). Since chromosomal aberrations frequently do not affect the phenotype of the carrier, in contrast to the negative influence on spermatogenesis, there is an obvious need for genomic sequencing to investigate the point mutations that may be responsible for the differences between the azoospermic and cryptozoospermic phenotypes observed in a family. Progeny from the same parents provide a unique opportunity to discover a novel genomic background of male infertility

Complex cytogenetic and molecular-genetic analysis of males with spermatogenesis failure

The chromosomal anomalies, microdeletions of AZF region of Y-chromosome and CFTR gene mutations have been studied among 80 infertile men with idiopathic spermatogenetic failure: 36 (45 %) patients with aspermia, 19 (24 %) patients with azoospermia and 25 (31 %) patients with severe oligoasthenoteratozoospermia. In total 30 % males with spermatogenetic failure genetic factor of infertility was observed. Karyotype anomalies were observed in 17.5 % of infertile men, within 16.2 % numerical and structural gonosomal anomalies and in 1.3 % – Robertsonian translocation were revealed. In 11 % males with spermatogenetic failure, Y-chromosome AZF region microdeletions were detected. The frequency of CFTR major mutation F508del among infertile men was 6.25 %. 5T allele of polymorphic locus IVS8polyT was detected in 7.5 % of examined men. The results obtained indicate the high complexity of cytogenetic and moleculargenetic studies of male infertility.Изучали аномалии хромосом, микроделеции AZF региона Y-хромосомы и мутации гена ТРБМ у 80 мужчин с идиопатическими нарушениями сперматогенеза, а именно: у 36 (45 %) пациентов с аспермией, 19 (24 %) пациентов с азооспермией и 25 (31 %) пациентов с олигоастенотератозооспермией IV степени. В общем у 30 % мужчин с нарушениями сперматогенеза установлены генетические факторы бесплодия. Нарушения кариотипа наблюдали у 17.5 % бесплодных мужчин, среди них у 16.2 % – количественные и структурные аномалии хромосом и у 1.3 % – робертсоновскую транслокацию. У 11 % мужчин с нарушениями сперматогенеза выявили микроделеции AZF региона Y хромосомы. Частота мажорной мутации F508del гена ТРБМ среди бесплодных мужчин составила 6.25 %. 5T аллель полиморфного локуса IVS8polyT выявили у 7.5 % обследованных мужчин. Полученные результаты свидетельствуют о высокой информативности комплексного цитогенетического и молекулярно-генетического исследования при мужском бесплодии