Frequency of Y chromosome microdeletions and chromosomal abnormalities in infertile Thai men with oligozoospermia and azoospermia

Aim： To investigate the possible causes of oligozoospermia and azoospermia in infertile Thai men, and to find the frequencies of Y chromosome microdeletions and cytogenetic abnormalities in this group. Methods： From June 2003 to November 2005, 50 azoospermic and 80 oligozoospermic men were enrolled in the study. A detailed history was taken for each man, followed by general and genital examinations. Y chromosome microdeletions were detected by multiplex polymerase chain reaction （PCR） using 11 gene-specific primers that covered all three regions of the azoospermic factor （AZFa, AZFb and AZFc）. Fifty men with normal semen analysis were also studied. Karyotyping was done with the standard G- and Q-banding. Serum concentrations of follicle stimulating hormone （FSH）, luteinizing hormone （LH）, prolactin （PRL） and testosterone were measured by electrochemiluminescence immunoassays （ECLIA）. Results： Azoospermia and oligozoospermia could be explained by previous orchitis in 22.3%, former bilateral cryptorchidism in 19.2%, abnormal karyotypes in 4.6% and Y chromosome microdeletions in 3.8% of the subjects. The most frequent deletions were in the AZFc region （50%）, followed by AZFb （33%） and AZFbc （17%）. No significant difference was detected in hormonal profiles of infertile men, with or without microdeletions. Conclusion： The frequencies of Y chromosome microdeletions and cytogenetic abnormalities in oligozoospermic and azoospermic Thai men are comparable with similarly infertile men from other Asian and Western countries.

The prevalence of azoospermia factor microdeletion on the Y chromosome of Chinese infertile men detected by multi-analyte suspension array technology

Aim： To develop a high-throughput multiplex, fast and simple assay to scan azoospermia factor （AZF） region microdeletions on the Y chromosome and establish the prevalence of Y chromosomal microdeletions in Chinese infertile males with azoospermia or oligozoospermia. Methods： In total, 178 infertile patients with azoospermia （nonobstructed）, 134 infertile patients with oligozoospermia as well as 40 fertile man controls were included in the present study. The samples were screened for AZF microdeletion using optimized multi-analyte suspension array （MASA） technology. Results： Of the 312 patients, 36 （11.5%） were found to have deletions in the AZF region. The rnicrodeletion frequency was 14% （25/178） in the azoospermia group and 8.2% （11/134） in the oligospermia group. Among 36 patients with microdeletions, 19 had deletions in the AZFc region, seven had deletions in AZFa and six had deletions in AZFb. In addition, four patients had both AZFb and AZFc deletions. No deletion in the AZF region was found in the 40 fertile controls. Conclusion： There is a high prevalence of Y chromosomal microdeletions in Chinese infertile males with azoospermia or oligozoospermia. The MASA technology, which has been established in the present study, provides a sensitive and high-throughput method for detecting the deletion of the Y chromosome. And the results suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.

Y chromosome microdeletions in azoospermic patients with Klinefelter's syndrome

Aim： To study the occurrence of Y chromosome microdeletions in azoospermic patients with Klinefelter＇s syndrome （KFS）. Methods： Blood and semen samples were collected from azoospermic patients with KFS （n = 14） and a control group of men of proven fertility （n = 13）. Semen analysis was done according to World Health Organization （WHO） guidelines. Blood samples were processed for karyotyping, fluorescent in situ hybridization （FISH） and measurement of plasma follicle stimulating hormone （FSH） by radioimmunoassay. To determine Y chromosome microdeletions, polymerase chain reaction （PCR） of 16 sequence tagged sites （STS） and three genes （DFFRY, XKRY and RBM1 Y） was performed on isolated genomic DNA. Testicular fine needle aspiration cytology （FNAC） was done in selected cases. Results： Y chromosome microdeletions spanning the azoospermia factor （AZF）a and AZFb loci were found in four of the 14 azoospermic patients with KFS. Karyotype and FISH analysis revealed that, of the four cases showing Y chromosome microdeletion, three cases had a 47,XXY/46,XY chromosomal pattern and one case had a 46,XY/47,XXY/48,XXXY/48,XXYY chromosomal pattern. The testicular FNAC of one sample with Y chromosome microdeletion revealed Sertoli cell-only type of morphology. However, no Y chromosome microdeletions were observed in any of the 13 fertile men. All patients with KFS had elevated plasma FSH levels. Conclusion： Patients with KFS may harbor Y chromosome microdeletions and screening for these should be a part of their diagnostic work-up, particularly in those considering assisted reproductive techniques. （Asian JAndrol 2006 Jan; 8： 81-88）

Multiplex PCR Screening of Y Chromosome Microdeletions in Azoospermic Patients

Objective To develop a multiplex PCR protocol for routine screening of microdeletions on the Y chromosome Methods Five multiplex sets were established and Y chromosome microdeletions screening were carried out in 26 azoospermic men who undertook ICSI and 30 azoospermic men who undertook testicular biopsy. Results In 56 azoospermic men, 5 patients were found with AZFc/DAZ microdeletions, 2 patients were accompanied by AZFc/DAZ and AZFb/RBM1 double microdeletion, and 1 patient had only single sY153 microdeletion. Conclusion The multiplex PCR protocol presented in this study is an easy and reliable method for detecting microdeletions on the Y chromosome. Routine screening for microdeletions on the Y chromosome in azoospermic patients is essential.

Y-chromosomal microdeletions and partial deletions of the Azoospermia Factor c(AZFc)region in normozoospermic,severe oligozoospermic and azoospermic men in Sri Lanka

Aim： To assess for the first time the occurrence of Y chromosomal microdeletions and partial deletions of the Azoospermia Factor c （AZFc） region in Sri Lankan men and to correlate them with clinical parameters. Methods： In a retrospective study, we analyzed 96 infertile men （78 with non-obstructive azoospermia） and 87 controls with normal spermatogenesis. AZFa, AZFb, AZFc and partial deletions within the AZFc region were analyzed by multiplex polymerase chain reaction （PCR） according to established protocols. Results： No AZFa, AZFb or AZFc deletions were found in the control group. Seven patients in the group of infertile men were found to have deletions as following： one AZFa, two AZFc, two AZFbc and two AZFabc. The relative distribution of these patterns was significantly different compared with that found in the German population. Extension analysis confirmed that the deletions occurred according to the current pathogenic model, gr/gr deletions were found to be equally present both in the patients （n = 4） and in the control group （n = 4）. One b2/b3 deletion was found in the patient group. Conclusion： These results suggest that the frequency and pattern of microdeletions of the Y chromosome in Sri Lankan men are similar to those found in other populations and confirm that gr/gr deletions are not sufficient to cause spermatogenetic failure. （Asian J Androl 2006 Jan; 8： 39-44）

Vertical transmission of the Yq AZFc microdeletion from father to son over two or three generations in infertile Han Chinese families

This study was carried out to analyze the vertical transmission of Yq AZFc microdeletions from father to son in infertile Han Chinese families to investigate genetic factors and family background affecting fertility status.The peripheral blood of infertile males in 19 Han families was extracted and screened with modified multiplex polymerase chain reaction （PCR）. Family trees were drawn according to fertility status and clinical characteristics of the subjects. The vertical transmission of Yq AZFc microdeletions was detected in six cases of 19 investigated families （31.6%,6/19）. Although both fathers and sons showed a similar type of Yq AZFc deletion,the fathers were fertile,whereas the sons were infertile and showed severe oligozoospermia. The vertical transmission of Yq AZFc microdeletion from fertile fathers to infertile sons over generations is not rare. This has different effects on fertility status in fathers and sons in Han Chinese families. Both genetic factors and family background affect spermatogenetic phenotypes.

Y microdeletions in the Istria county,Croatia

Aim:To establish the frequency of Y chromosome microdeletions in an unselected group of infertile Croatian men. Methods:An unselected group of 105 patients (male partners of infertile couples),both with idiopathic and non- idiopathic infertility,consecutively referred to the outpatient infertility clinic,gynecology department,General Hospital Pula,Istria County,Croatia,was examined for the presence or absence of Y chromosome microdeletions by poly- merase chain reaction analysis.Results:One of the 105 men (0.95 %,95 % CI=0.17-5.2 %) was found to have a microdeletion.Conclusion:A low frequency of Y chromosome microdeletions was found in the group of unselected infertile Croatian men.

Implications of Cytogenetic Abnormalities and Azoospermia Factor Microdeletions in Assisted Procreation

Assisted procreation techniques have revolutionized the management of infertility and have offered hope to millions of infertile couples. The main aim of these procedures is to produce healthy offspring. However recent studies on short term outcome of ART have reported a higher incidence of low birth weight, development delay, imprinting defects, sex and autosomal structural abnormalities, major and minor congenital malformation and certain cancers in babies conceived via ART. Further the health of ART conceived children beyond the neonatal period have been less well evaluated. A large number of infertile couples opting for ART have an underlying genetic aetiology. These genetic aberrations are iatrogenitically transmitted via ART. Thus it is important that all couples undergo a detailed and comprehensive genetic evaluation prior to ART.

Yq AZF microdeletions in male infertility:An update on the phenotypic spectrum,epidemiology and diagnostics

According to the latest data,globally 15%of couples have infertility and male infertility contributes to 10%of all cases.Infertility can be caused by certain biological changes in the gonads and the reproductive system like azoospermia,oligospermia,asthenospermia,teratozoospermia and hypospermatogenesis.Genetic causes of azoospermia include chromosomal abnormalities,Y chromosome microdeletions and deletion or other mutations of Y-linked genes.The maximum number of the genes are located in the azoospermia factor region of the long arm(Yq)of the Y chromosome.Y chromosome microdeletion is known as the second major genetic cause of spermatogenetic failure.This article aims to review the latest updates on the involvement of Yq microdeletions in male infertility.The diagnostics,prevalence and phenotypic spectrum related to Yq gene microdeletions are discussed.

Fiber-fluorescence in situ hybridization analyses as a diagnostic application for orientation of microduplications

Microduplications are normally invisible under microscopy and were not recognized before chromosomal microarray testing was available. Although it is difficult to confirm the orientation of duplicated segments by standard fluorescence in situ hybridization(FISH), our data indicates that fiber-FISH analysis has the potential to reveal the orientation of duplicated and triplicated segments of chromosomes. Recurrent microduplications reciprocal to microdeletions show tandem orientations of the duplicated segments, which is consistent with a non-allelic homologous recombination mechanism. Several random duplications showed tandem configurations and inverted duplications are rare. Further analysis is required to fully elucidate the basic mechanisms underlying such duplications/triplications.

Y染色体微缺失检测试剂盒行业标准的建立

目的建立Y染色体微缺失检测试剂盒行业标准。方法选择9个厂家的Y染色体微缺失检测试剂盒,统一发放Y染色体微缺失检测参考品,按照拟定的行业标准,对外观、检测限、阳性参考品符合率、阴性参考品符合率和重复性项目进行验证。结果8个试剂盒的全部项目的检测结果均满足要求。检测限和阳性参考品符合率项目中,仅试剂盒8未检出AZFa微缺失,不满足要求。结论大部分验证结果均能满足拟定行标中的要求,表明行业标准各指标具有一定的合理性,可操作性强。Y染色体微缺失检测试剂盒行业标准的建立将有助于规范这类试剂盒发展,提升质量,并为监管提供技术支持。

贵州苗族非梗阻性无精男性3例的Y染色体微缺失及致病候选基因

目的研究贵州苗族无精症男性的Y染色体微缺失和致病候选基因突变。方法本研究招募苗族非梗阻性无精症男性3人,使用目标区域捕获测序及全外显子测序,分析注释到相关基因区域,解析苗族无精症男性的Y染色体微缺失及致病候选位点。结果3例苗族非梗阻性无精症患者中未发现Y染色体微缺失位点。全外显子测序结果发现USP9Y、CFTR、ZMYND15、DNAH1的突变位点,可能是苗族非梗阻性无精症的候选致病突变。结论贵州苗族男性Y染色体微缺失阴性的非梗阻性无精症可能具有特异的基因致病突变位点,在男性不育研究及临床中应引起关注。

染色体微阵列分析技术对16p11.2综合征的诊断及遗传学分析

目的探索16p11.2微缺失/微重复综合征患者的临床症状和染色体微阵列技术(CMA)检测的遗传学变异。方法对2019年1月至2022年8月于宁波市妇女儿童医院就诊并接受CMA检测的16p11.2综合征患者的临床指征、遗传学结果、家系调查及妊娠结局进行描述性分析。结果发现22例患者(20例胎儿、2例患儿)的16p11.2核心区域拷贝数变异,16p11.2综合征的整体检出率为0.226%。其中8例胎儿超声异常(2例脊椎发育异常、1例泌尿系统异常、3例颈部透明层增厚、2例肠道回声增强),3例无创DNA结果异常,4例血清学筛查高风险,4例高龄妊娠。22例中10例行亲本验证,其中新发突变7例,遗传自母亲2例,遗传自父亲1例。另有1例胎儿核型异常,验证后遗传自母亲。20例胎儿中,9例活产分娩,1例诊断为先天性心脏病,语言发育迟缓,其余生长发育未见异常。2例患儿携带缺失片段,临床表现为全面性强直阵挛发作,其中1例合并生长发育迟缓。结论16p11.2综合征患者的骨骼、心脏、神经、泌尿系统以及语言发育异常,临床表型呈异质性与多样性,产前诊断仍需积累大量临床数据。

15例Xp22.3微缺失/微重复胎儿的临床诊断和分子遗传学分析

目的:探讨Xp22.3微缺失/微重复的基因型与临床表型的相关性。方法:对15例SNP-array检测结果为Xp22.3微缺失/微重复病例的分子遗传学特征、临床表型和随访信息进行回顾性分析。结果:15例Xp22.3微缺失/微重复胎儿中,8例为微缺失病例(8/15),片段大小165~5.1Mb,片段内基因包括SHOX、ARSE、STS、ANOS1、NLGN4X、GPR143等30个OMIM基因,其中SHOX、ARSE、STS、ANOS1为单倍剂量不足基因。7例(7/15)为微重复病例,片段大小为229~1.7Mb,片段内基因包括SHOX、ARSE、ANOS1、STS、NLGN4X、GPR143等23个OMIM编码基因,不含三倍剂量敏感基因。8例微缺失病例中7例诊断为致病性拷贝数变异(CNV),1例诊断为临床意义不明(VOUS);7例微重复病例均诊断为VOUS。15例胎儿中7例(7/15)超声发现异常特征,其中四肢短小3例(3/7),唇腭裂1例(1/7),心血管异常1例(1/7),侧脑室增宽1例(1/7),鼻骨缺如1例(1/7)。对12例病例进行了亲本来源验证,5例(5/12)为母源性遗传,3例为父源性遗传(3/12)。15病例中4例(4/15)微缺失选择终止妊娠,1例稽留流产,均为男性胎儿;10例(10/15)选择继续妊娠,除1例新生儿左耳听力受损外,其余随访均无异常。结论:Xp22.3微缺失因涉及SHOX、ARSE、STS、ANOS1等单倍剂量敏感基因,为致病性CNV,表现为生长发育迟缓、软骨发育不全等症状。Xp22.3微重复无三倍剂量敏感基因,定义为VOUS,胎儿妊娠结局良好。当SNP-array诊断为Xp22.3微缺失/微重复时,应对其基因组信息与临床表型相关性进行分析,为孕妇提供指导。

Relationship between microdeletion on Y chromosome and patients with idiopathic azoospermia and severe oligozoospermia in the Chinese

Objectives To evaluate the relationship between microdeletion or mutation on the Y chromosome and Chinese patients with idiopathic azoospermia and severe oligozoospermia and to establish a molecular detection method.Methods Microdeletion or mutation detection at the AZFa (sY84 and USP9Y), AZFb, AZFc/DAZ and SRY regions of the Y chromosome. Seventy-three azoospermia and 28 severe oligozoospermia patients were evaluated using PCR and PCR-SSCP techniques.Results Twelve of 101 patients (12%) with the AZFc/DAZ microdeletion were found, including 8 with azoospermia (11%) and 4 with severe oligozoospermia (14.3%), and 1 patient had a AZFb and AZFc/DAZ double deletion. No deletions in the AZFa or SRY regions were found. No deletions in AZFa, AZFb, AZFc/DAZ or SRY regions were found in 60 normal men who had produced one or more children.Conclusions Microdeletion on the Y chromosome, especially at its AZFc/DAZ regions, may be a major cause of azoospermia and severe oligozoospermia leading to male infertility in China. It is recommended that patients have genetic counseling and microdeletion detection on the Y chromosome before intracytoplasmic sperm injection.

NIPT筛查胎儿患猫叫综合征的初探

目的初步探讨无创产前基因检测(NIPT)筛查胎儿患猫叫综合征临床性能。方法收集2018年4月—2019年3月行NIPT提示胎儿患猫叫综合征高风险的孕妇,并收集其羊水细胞培养染色体核型分析或微阵列芯片检测结果,分析NIPT与羊水产前诊断结果的符合率。结果NIPT提示猫叫综合征病例11例,孕妇均接受了羊水穿刺,染色体核型分析或微阵列芯片检测出胎儿染色体异常6例,符合率为54.5%。结论NIPT对胎儿猫叫综合征的筛查具有临床价值,当提示高风险时必须行有创性产前诊断。

核型正常产前诊断中染色体微阵列的应用分析

目的 探讨染色体微阵列(CMA)在核型正常的羊水产前诊断中染色体微缺失或微重复的临床意义。方法 收集2017年1月至2021年6月在汕头大学医学院附属粤北人民医院行羊膜腔介入性产前诊断的877例羊水标本,进行核型及CMA检测,以核型正常的794例羊水标本为研究对象,对CMA检测的异常结果进行分析。结果 在794例核型正常的标本中,CMA检测异常35例,产前诊断指征中,胎儿超声异常13例,占37.14%(13/35);血清学筛查高风险10例,占28.57%(10/35);高龄妊娠6例,占17.14%(6/35);无创产前检测(NIPT)提示异常3例,不良孕产史3例。CMA检测较核型分析额外检出4.41%(35/794)的异常标本;其中,致病性拷贝数变异(CNVs)17例,检出率为2.14%(17/794),临床意义不明CNVs 12例,检出率为1.51%(12/794),纯合区域(ROH)异常6例,检出率为0.76%(6/794)。在17例致病性CNVs中,检出的CNVs片段范围在147.00kb~4.30Mb,检出5种已知微缺失/微重复综合征,分别为16p11.2微重复综合征、16p13.11微缺失综合征、肾囊肿和糖尿病(RCAD)综合征、22q11.21微重复综合征、DiGeorge综合征。在12例临床意义不明CNVs中,检出的CNVs片段范围在369.00kb~5.70Mb,对7例胎儿的父母进行了外周血CMA验证,其中4例(编号18、编号19、编号23、编号29)遗传自表型正常的母亲,2例(编号22、编号28)遗传自表型正常的父亲,1例(编号20)考虑为新发病例。在6例ROH异常的CNVs中,检出的CNVs片段范围在21.80~83.00Mb,对2例胎儿的父母进行了外周血CMA验证,其中1例(编号32)排除了20号染色体单亲二倍体(UPD)的可能,1例(编号33)仅对母亲进行了CMA验证,其结果显示正常,考虑为父源性。结论 CMA检测可以检出核型分析难以测查的微缺失、微重复、单亲二倍体及杂合性缺失等基因组失衡现象,是产前诊断核型分析的有效补充检测技术。

颈项透明层增厚胎儿中拷贝数变异的分析

目的分析颈项透明层(nuchal translucency,NT)增厚胎儿中拷贝数变异(copy number variations,CNV)的检出率和特点,以及NT增厚与CNV的关系。方法选取2017年1月至2021年12月在内蒙古自治区妇幼保健院经孕早期超声检查NT≥2.5 mm,且后续接受介入性产前诊断的334例单胎孕妇及其胎儿为研究对象,收集其产检信息、遗传学检测结果及妊娠结局。遗传学检测方法包括G显带核型分析和染色体微阵列分析(chromosomal microarray analysis,CMA)。按NT厚度、NT合并其他染色体异常高危因素分别分组分析不同临床特征下NT增厚与CNV发生率的关系。结果①共发现26例CNV,检出率为7.78%。其中,13例为致病性CNV,2例为可能致病性CNV,11例为临床意义未明的(variant of uncertain significance,VOUS)CNV。15例中13例致病性及可能致病性CNV终止妊娠,11例中9例VOUS CNV病例活产并正常发育。②不同NT厚度组间CNV的检出率,以及单纯NT增厚与NT增厚合并其他高风险因素间CNV检出率均差异无统计学意义。③26例中有9例(34.6%)为复发性微缺失微重复区域的CNV,其中5例在15q11.2区域和3例在16p12.2-13.1区域。结论CNV是NT增厚胎儿常见的遗传变异,且多数为致病性和可能致病性CNV。但NT增厚程度及是否合并其他产前筛查高危因素与CNV的发生率无明显相关性。复发性微缺失微重复区域的CNV出现频率较高值得引起关注。

核型分析、BoBs、CNV和Y染色体AZF微缺失检测在羊水染色体鉴定中的应用

目的探讨染色体核型分析、细菌人工染色体标记-微球鉴别/分离法(bacterial artificial chromosome on beads,BoBs)、基因拷贝数目变异检测(copy number variations,CNV)和Y染色体无精子症因子(azoospermia factor,AZF)微缺失联合检测在孕妇羊水染色体鉴定中的应用价值。方法选取2021年7月至2022年12月于皖南医学院第一附属医院(弋矶山医院)产前诊断中心就诊中符合产前诊断指征的孕妇507例,抽取孕16~25 w羊水,分别进行细胞培养染色体核型分析,提取DNA进行BoBs检测,对其中1例21-三体综合征和1例标记染色体进行CNV验证,2例Y染色体进行AZF微缺失验证,统计结果。结果507例羊水穿刺指征统计,以唐筛高风险占比最高,达39.1%(198/507);NIPT高风险组仅占总检查孕妇的14.0%(71/507),但核型分析和BoBs异常结果占比最高,分别占全部异常结果的40.3%(23/57)和47.7%(21/44)。507例羊水标本一共检出异常结果59例(11.6%),其中染色体核型分析检出异常57例(11.2%),常染色体数目异常26例(5.1%),常染色体结构异常14例(2.8%);性染色体数目异常13例(2.6%),性染色体结构异常4例(0.7%)。BoBs检出异常44例(8.7%),其中常染色体数目异常26例(5.1%),性染色体数目异常14例(2.8%),性染色体部分缺失2例(0.4%),检出46,XN,22q11重复2例(0.4%)。BoBs与核型分析结果比对,常染色体和性染色体数目异常结果符合率分别为100.0%和99.8%。另外BoBs将其中1例46,X,del(Y)(q11)判读为45,XO,1例47,XN,+mar[50]/46,XN[10]判读为46,XN,其余染色体结构异常不在BoBs检测范围。CNV验证致病性拷贝数变异1例,临床意义未明拷贝数变异1例;Y染色体AZF微缺失验证2例Y染色体为SRY+,存在AZFb+c缺失。结论羊水染色体核型分析能够发现染色体数目和结构异常核型,对于未知来源的标记染色体和<10 Mb的微缺失/微重复缺乏优势。BoBs对于常染色体数目检测和微缺失/微重复检测具有优势,能提示性染色体片段缺失,但要注意对性染色体的误判,常染色体结构异常不在BoBs检测范围。CNV对于全基因组微缺失和微重复检测具有优势。Y染色体AZF微缺失检测可对Y染色体进行验证。联合应用上述检测技术,能对羊水染色体数目和结构异常提供多方位诊断,值得推广应用。