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.

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.

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.

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.

Microdeletions and vertical transmission of the Y-chromosome azoospermia factor region

Spermatogenesis is regulated by several Y chromosome-specific genes located in a specific region of the long arm of the Y chromosome,the azoospermia factor region(AZF).AZF microdeletions are the main structural chromosomal abnormalities that cause male infertility.Assisted reproductive technology(ART)has been used to overcome natural fertilization barriers,allowing infertile couples to have children.However,these techniques increase the risk of vertical transmission of genetic defects.Despite widespread awareness of AZF microdeletions,the occurrence of de novo deletions and overexpression,as well as the expansion of AZF microdeletion vertical transmission,remains unknown.This review summarizes the mechanism of AZF microdeletion and the function of the candidate genes in the AZF region and their corresponding clinical phenotypes.Moreover,vertical transmission cases of AZF microdeletions,the impact of vertical inheritance on male fertility,and the prospective direction of research in this field are also outlined.

Y chromosome microdeletion screening using a new molecular diagnostic method in 1030 Japanese males with infertility

The azoospermia factor(AZF)region is important for spermatogenesis,and deletions within these regions are a common cause of oligozoospermia and azoospermia.Although several studies have reported this cause,the present research,to the best of our knowledge,is the first large-scale study assessing this factor in Japan.In this study,1030 male patients with infertility who were examined for Y chromosome microdeletion using the polymerase chain reaction-reverse sequence-specific oligonucleotide(PCR-rSSO)method,a newly developed method for Y chromosome microdeletion screening,were included.The study enrolled 250 patients with severe oligospermia and 717 patients with azoospermia.Among the 1030 patients,4,4,10,and 52 had AZFa,AZFb,AZFb+c,and AZFc deletions,respectively.The sperm recovery rate(SRR)of microdissection testicular sperm extraction in patients with AZFc deletions was significantly higher than that in those without AZF deletions(60.0%vs 28.7%,P=0.04).In patients with gr/gr deletion,SRR was 18.7%,which was lower than that in those without gr/gr deletion,but was not statistically significant.In conclusion,our study showed that the frequency of Y chromosome microdeletion in male patients in Japan was similar to that reported in patients from other countries,and SRR was higher in patients with AZFc deletion.

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）

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.

Screening for Y chromosome microdeletions in idiopathic and nonidiopathic infertile men with varicocele and cryptorchidism

Cytogenetic and molecular studies of azoospermic and oligozoospermic males have suggested the presence of azoospermia factors （AZF） in the Y chromosome. Deletion in AZF regions has been reported to disrupt spermatogenesis and cause infertility. Several candidate genes responsible for spermatogenesis have been identified in this region and some of them are thought to be functional in human spermatogenesis. And we reported clinical and molecular studies of Y chromosome microdeletions in Chinese. This study aimed at assessing the frequency of microdeletions in Chinese men with idiopathic and nonidiopathic infertility problems and dicussing the clinical significance of the AZF region.

Genetics and male infertility

The goal of this review is to explain the requirement for understanding the genetic structure of infertility arising from male factor and to discuss the essentials of these genetic elements(2). The majority of the population is affected by this disorder caused by male factor infertility(1); but the etiologies are still unknown. After the primary genetic structure in infertile phenotypes is searched, an evaluation can be made. Thus the reasons causing infertility can be discovered and patients can benefit from effective therapies(1). Publications about male infertility within the recent 10 years in the Pubmed database were discussed(1). There are some approachments for describing the function of specificgenes, but no adequate study is present to be useful for diagnosing and treating male infertility(1). Male fertility and fertility in offspring of males are considerably affected by the exact transition of epigenetic information(1). When the genetic factors playing a role in male infertility were analysed, significant steps will be taken for treating patients and determining the reasons of idiopathic infertility(1). Developments in technology associated with the impact of genetics may enable to specify the etiology of male infertility by determining specific infertile phenotype marks(1).

赤峰地区男性不育患者Y染色体微缺失的检测分析

目的:探讨赤峰地区男性不育患者Y染色体微缺失的检测效果。方法:选取2022年1月—2023年7月赤峰学院附属医院收治的男性不育患者150例为研究对象,结合诊断结果将其分为初诊不孕不育组、精子状态异常组、睾丸发育异常组,各50例。三组患者均进行Y染色体微缺失检测。比较三组检测结果。结果:睾丸发育异常组患者的Y染色体微缺失率高于初诊不孕不育组、精子状态异常组,差异有统计学意义(P<0.05)。AZFa位点、AZFb位点的缺失例数是0,AZFc位点的缺失例数是16例,AZFbc位点的缺失例数是1例,AZFabc位点的缺失例数是1例;初诊不孕不育组、精子状态异常组、睾丸发育异常组的缺失位点均以AZFc为主。结论:初诊不孕不育、精子状态异常、睾丸发育异常患者容易出现Y染色体AZFc位点缺失现象。

1338例男性无精症或少精症患者Y染色体微缺失分析

目的探讨男性无精症或少精症患者的Y染色体微缺失情况。方法1338例男性不育患者按照精液常规检查结果分为无精症组、严重少精症组、少精症组,选取同期320例健康男性为正常对照组,应用荧光定量PCR技术进行AZF区微缺失分析。结果无精症组和严重少精症组的Y染色体微缺失发生率均显著高于正常对照组(P<0.05)。在入组的研究对象中,AZFc位点缺失在男性不育中占比最高,为4.9%。在118例Y染色体微缺失患者中,共有25例染色体核型异常,其中以47,XXY核型占比最高,为8.5%。结论Y染色体微缺失检测是男性少精症或无精症等的首选临床检测项目,对男性不育的诊断有重要的指导价值。

男性不育患者Y染色体AZF区域STS微缺失位点多重PCR法检测及其意义

目的:探讨Y染色体无精子症因子(AZF)区域的15个标签位点(STS)序列片段微缺失位点与男性不育(MI)的关系,为干预遗传性MI提供依据。方法:选择2 586例疑似MI患者作为研究对象,按照年龄分为≤20岁组(14例)、21~30岁组(988例)、 31~40岁组(1 318例)和≥41岁组(266例)。采用聚合酶链式反应(PCR)法对Y染色体AZF区域的15个STS序列片段进行检测并筛选异常结果,比较各组MI患者Y染色体微缺失情况。结果:在2 586例参检人群样本中发现207例Y染色体异常,占总体样本的8.00%;其中≤20岁组、21~30岁组、31~40岁组和≥41岁组检出Y染色体异常率分别为7.14%(1/14)、8.10%(80/988)、8.04%(106/1 318)和7.52%(20/266);各组患者基础位点合并扩展位点的缺失率比较差异有统计学意义(χ^(2)=10.836,P=0.013),21~30岁组患者基础位点合并扩展位点的缺失率明显高于31~40岁组(P<0.05);在总体受检样本中,发生基础位点片段缺失者52例,异常率为2.01%,各组患者异常率比较差异有统计学意义(χ^(2)=9.658,P=0.022);AZFc片段缺失者占所有受检人数1.39%,21~30岁组和31~40岁组患者AZFc缺失率明显高于≥41岁组(P<0.05),21~30岁组和31~40岁组患者总体缺失率比较差异有统计学意义(χ^(2)=3.612, P=0.040);各组患者sY127、 sY134合并sY105、 sY121、 sY1192、 sY153和sY160位点缺失率比较差异无统计学意义(P>0.05),各组患者sY254、sY255合并sY105、sY121、sY1192、sY153和sY160位点缺失率比较差异无统计学意义(P>0.05)结论:广西壮族自治区东北部地区主要生育年龄段男性Y染色体异常的主要原因是sY1192和sY153位点微缺失,其中以sY1192位点微缺失为主,且随着年龄增长,该位点突变检出率越高。

对无精子症和严重少精子症患者Y染色体畸变和微缺失的研究及评估

目的研究无精子症和少精子症患者染色体畸变及Y染色体(Yq11区)无精子症因子(azoospermicfac-tor,AZF)微缺失情况,建立Y染色体微缺失的临床筛查方法。对原发性无精子及少弱精症患者与AZF微缺失的关系。方法对145例患者(无精子症102例,严重少精子症43例)经染色体核型分析及AZF的3个位点8对引物PCR扩增,检测染色体畸变和Y染色体微缺失率。选取6个Y染色体特异性序列标签位点(STS),用PCR技术检测145例精子发生障碍患者AZF区微缺失情况。结果145例中染色体核型异常12例,占8.3%。AZF区微缺失21例,缺失率为14.5%。无精子症和严重少精子症AZF缺失率分别为14.70%和11.62%。145例中AZF区微缺失21例,表现为无精子症。缺失均在AZFc区,7例为DAZ(sY254、sY255)缺失,另2例为DNA加sY157缺失。结论染色体畸变和Y染色体微缺失是导致无精子症和严重少精子症的主要原因之一。无精子症缺失率高于严重少精子症患者。AZF3个位点8对引物PCR扩增可作为Y染色体微缺失的临床筛查方法。

特发性无精症和严重少精症患者Y染色体微缺失的分子检测

目的 :研究特发性无精症和严重少精症患者与 Y染色体微缺失的关系 ,建立无精症和严重少精症患者 Y染色体微缺失的分子检测方法。方法 :应用 PCR技术对 1 0 0例无精症和严重少精症患者 (其中无精症 72例 ,严重少精症 2 8例 )进行 Y染色体 AZFa、AZFb、AZFc/DAZ、SRY的微缺失检测。结果 :1 2例患者 (1 2 % )有 AZFc的微缺失 (其中无精症 8例 ,占 1 1 .1 % ;严重少精症 4例 ,占 1 4.3% ) ,且其中 1例无精症患者为 AZFb、AZFc双重缺失 ;所有病例未发现有 AZFa的缺失 ;SRY基因 PCR扩增均为阳性。6 0例已有生育的正常男性均无 AZFa、AZFb、AZFc、SRY微缺失。结论 :Y染色体微缺失 ,特别是 AZFc/DAZ的缺失是引起无精和严重少精、造成男性不育的重要原因之一 ,在进行遗传咨询和行卵细胞质内注入精子术 (ICSI)时 ,有必要对不明原因的不育男性患者进行

中国无精症、严重寡精症患者的染色体异常和Y染色体微缺失(英文)

染色体异常和 Y 染色体微缺失被认为是两个白种人群中常见的生精障碍相关遗传因素。为了解中国无精症、严重寡精症患者中的染色体异常和 Y 染色体微缺失,运用染色体 G 显带技术,在 358 个原发无精症(256 人)和严重寡精症(102人)不育患者中进行染色体核型分析;同时运用多重 PCR 技术,在核型正常的患者和 100 个正常生育男性中,对 Y 染色体 AZF 区微缺失进行筛查。在 358 个患者中,39 人(10.9%)发现有染色体异常,Klinefelter(47, XYY) 最为常见。无精症患者性染色体异常频率明显高于严重寡精症患者 (12.1% vs 1%)。在 319 个核型正常的患者中,46(14.4%)发现有AZF 区微缺失,无精症和寡精症患者中 Y 染色体微缺失频率分别为 15%和 13.1%,AZFc 区的微缺失最为常见,AZFa 区的微缺失只见于无精症患者,正常生育男性中未发现 AZF 区的微缺失。结果显示,在中国无精症、严重寡精症患者中,大约 25%的患者有染色体异常或 Y 染色体 AZF 区微缺失,提示这两种遗传异常是中国人群生精障碍的重要相关遗传病因,有必要在男性不育的诊断以及利用细胞浆内精子注射技术进行辅助生育时,对患者的这些遗传异常进行筛查。

Y染色体微缺失人群中Y-STR等位基因缺失模式分析

Y染色体短串联重复序列(Y-short tandem repeats, Y-STRs)已被广泛应用到DNA检验领域。然而,由于Y染色体存在较高的结构突变率,可能会导致部分Y-STR等位基因丢失甚至产生特殊的缺失模式,从而影响其在法医学中的应用。位于Y染色体长臂的无精子症因子(azoospermia factor, AZF)与精子发生有关,该区域微缺失可导致不育症。然而Y染色体微缺失人群是否存在特殊的Y-STR缺失模式仍有待研究。本文利用法医学上常用17个Y-STR探讨了85例Y染色体微缺失患者的Y-STR缺失模式。结果显示,单纯AZF a区缺失样本,均存在DYS439-DYS389I-DYS389II基因座无效扩增情况;单纯AZF b区或单纯AZF c区缺失样本存在DYS448基因座无效扩增;复合AZF b+c+d区缺失样本存在DYS385-DYS392-DYS448基因座无效扩增;复合AZFa+b+c+d区缺失样本存在DYS390-Y-GATA-H4-DYS385-DYS392-DYS448基因座无效扩增。因此,本研究结果提示Y-STR缺失模式与Y染色体微缺失有对应关系。

精索静脉曲张男性不育患者Y染色体微缺失检测

目的:探讨精索静脉曲张(varicocele,VC)不育患者Y染色体微缺失特点及其与临床表型的关系,为评价VC不育患者是否行手术治疗或ICSI提供依据。方法:VC不育患者174例,分为3组,A组:无精子症47例;B组:严重少精子症57例;C组:轻度少精子症70例;设立正常生育的健康志愿者男性28例作为对照组(D组)。抽取外周血提取DNA,选取Y染色体上AZFa、AZFb、AZFc区共6个序列标签位点,应用多重PCR进行扩增;已生育女性26例作为阴性对照,分别运用琼脂糖凝胶电泳分离,对照阅读扩增产物,判定有无缺失存在以及缺失类型。结果:174例男性不育患者中有22例检测到Y染色体微缺失,缺失率12.64%;A组11例存在微缺失,B组11例存在微缺失,C组未检测到微缺失。A组与C组、B组与C组比较,差异均有显著性。A组缺失病例中有6例为AZFc区缺失,1例为AZFa缺失,2例为AZFb区缺失,2例为AZFb、AZFc区共同缺失;B组缺失病例中有8例为AZFc缺失,2例为AZFb缺失,1例为AZFb、AZFc区共同缺失。结论:①精液异常VC不育与Y染色体微缺失有关;②VC不育患者特别是无精子症和严重少精子症患者,应该进行Y染色体微缺失的检测。

QF-PCR筛查男性不育患者Y染色体无精子症因子微缺失

为评估定量荧光PCR(Quantitative fluorescent polymerase chain reaction,QF-PCR)技术在快速筛查无精子症因子(Azoospermia factor,AZF)微缺失中的应用,文章对1218例非梗阻性无精子症、少精子症的男性不育患者,采用多重QF-PCR结合毛细管电泳技术,检测Y染色体长臂AZF区9个序列标签位点(Sequence tagged site,STS)以及性染色体短臂的AMEL(Amelogenin)和SRY(Sex-determining region of Y chromosome)位点,辅以常规染色体G显带方法进行核型分析。结果显示,1218例患者中105例可见AZF区微缺失(8.62%),其中AZFc区缺失(67.62%)最常见,其次为AZFb,c区缺失(20.95%);AZFb区缺失(7.62%)和AZFa区缺失(3.81%)则较少见;另有5例患者为AZFa,b,c区缺失合并AMEL-Y缺失,提示可能缺少Y染色体,经核型分析验证为46,XX(性反转)。105例AZF区微缺失患者的染色体核型分析显示染色体异常16例,其中"Yqh-"12例。根据AMEL-X/AMEL-Y比值,可见1218例患者中86例可能存在性染色体异常,经核型分析验证,68例为性染色体非整倍体。多重QF-PCR技术,一个反应即能检测样本的多个位点,并可提示性染色体是否存在异常,有助于男性不育患者尽早明确病因,也为后续的检查和治疗提供依据。