Y chromosome microdeletions and germinal mosaicism in infertile males

Molecular deletions of the Y chromosome long arm are a frequent cause of male infertility. Because these deletions are thought to be inherited from fathers without Y chromosome deletions, the question arises as to whether their relatively high incidence in the male population could be due to the existence of a mosaicism in somatic and/or germinal paternal cells. This study included a total of 181 infertile men, among whom 18 were found to have an abnormal karyotype. In the other 163, polymerase chain reaction (PCR) analysis detected nine (5.5%) Y chromosome microdeletions. Blood, spermatozoa or testicular cells from 47 men (27 oligozoospermia, 20 azoospermia), including six Y-deleted patients, were screened for mosaicism using double target fluorescence in-situ hybridization (FISH) with Y centromeric and deleted in azoospermia (DAZ) gene-specific probes. Results indicated that: (i) percentages of double (intact Y chromosome) or single (deleted Y chromosome) fluorescent signals by FISH were in agreement with PCR data, thus demonstrating the reliability of the method; and (ii) a weak germ cell mosaicism was found in only two oligozoospermic patients, carrying 1.97 and 4.13% respectively of spermatozoa with a deleted Y chromosome. Further studies on larger populations are needed to evaluate precisely the incidence of Y deletion mosaicisms in infertile men.     

Ultrastructural sperm study in infertile males with microdeletions of Y chromosome

A retrospective study to detect specific Y chromosome microdeletions and to evaluate sperm ultrastructural characteristics in infertile men was set up. We selected 219 infertile men referred to Regional Referral Center for Male Infertility, Siena, Italy for semen analysis from January 1999 to April 2004. Family history, lymphocyte karyotype determination, Y microdeletion screening, physical examination, hormonal assays, semen analysis were carried out. Sperm concentration and progressive motility, ultrastructural analysis of sperm organelles, PCR amplification of sequence tagged sites for Y microdeletion screening were performed. Different Y-chromosome deletions were found, mainly in the AZFb and AZFc regions. Severe alterations of sperm ultrastructure, affecting whole sperm population, were detected in carriers of Y-deletions. Our data confirms the highest frequency of Y deletions in azoospermic patients. In all other patients with Y microdeletions, sperm ultrastructural defects affected the whole sperm population and were mainly related to apoptosis or immaturity.     

200例男性不育患者的Y染色体微缺失检测

目的探讨男性不育患者与Y染色体微缺失之间的关系。方法利用15个Y染色体特异序列标签位点,以多重PCR法检测男性不育患者的Y染色体微缺失情况。结果 200例男性不育患者中共检出Y染色体微缺失7例,缺失率为3.5%。其中单纯A;ZFc缺失2例,缺失率为1%(2/200);A;ZFb缺失率为3例,缺失率为1.5%(3/200);单纯A;ZFa缺失2例,缺失率为1%(2/200),尚未发现联合缺失或大片段缺失患者。精液正常者(对照组)30例未发现Y染色体微缺失。结论 Y染色体微缺失是造成男性不育的常见病因之一。     

不育患者Y染色体AZF微缺失的分析

目的探讨Y染色体上AZF区域微缺失与男性不育的关系。方法采用多重PCR技术,对20例不育患者AZF4个区的l5个序列标签位点（STS）进行了微缺失检测和细胞遗传学检查。结果20例患者中共有3例发现微缺失（15%）。结论AZF微缺失是导致男性不育的重要原因之一,细胞遗传学检查与AZF微缺失无相关性。     

男性不育患者Y染色体AZF基因微缺失检测

目的探讨原发性无精子症、严重少精子症及少精子症患者与Y染色体无精子因子（azoospermia factor,AZF）区微缺失的关系。方法采用多重PCR方法对对照组192例已正常生育男性和实验组448例男性不育患者进行AZF区域内的15个序列标签位点（STS）的检测。结果对照组未发现AZF基因微缺失,实验组448例患者检测出五种AZF微缺失类型共41例,总缺失率为9.2%（41/448）,其中无精子症、严重少精子症和少精子症患者的缺失率分别为12.0%（19/158）、10.8%（17/157）、3.8%（5/133）,无精子症和严重少精子症患者Y染色体AZF微缺失率明显高于少精子症组,差别有统计学意义（P〈0.05）。使用15个STS位点进行检测其检出率较利用欧洲男科学会（European Academy of Andrology,EAA）推荐的6个STS位点提高约14%（5/36）。结论AZF微缺失是引起原发性无精子症、严重少精子症和少精子症的重要原因之一;增加STS位点检测数有利于提高AZF微缺失的检出率。     

染色体核型异常男性不育患者Y染色体微缺失分析

目的探讨染色体核型异常与Y染色体微缺失之间的关系。方法578例男性不育患者均来自2007年6月至2008年5月吉林省生殖医学研究所临床门诊。所有患者临床表现均为无精子症或严重少精子症。外周血淋巴细胞培养常规染色体标本制备,进行染色体核型分析。应用多重聚合酶链反应技术,采用无精子因子区9个序列标签位点对所有染色体异常的无精子症或严重少精子症患者进行Y染色体微缺失分析。结果578例遗传咨询患者中,检测出染色体核型异常患者62例,异常率为10.73%。其中包括无精子症或严重少精子症患者10例,占总样本1.73%。10例染色体核型异常患者检测出Y染色体微缺失2例,占20%。核型为46,XX/47,XX,＋del（Y）（q11）患者临床表现为睾丸小,无精症,Y染色体缺失位点为sY157、sY152、sY254、sY255;核型为45,X,-Y,-15,＋t（Y：15）（p？;q11）患者临床表现为特发性无精子症,缺失位点为sY143、sY254、sY255。结论涉及到Y染色体的染色体核型异常与AZF微缺失密切相关。     

180例无精子症或严重少精子症不育男性的Y染色体微缺失检测

目的探讨不育男性无精子症或严重少精子症与Y染色体微缺失之间的关系.方法利用9个Y染色体特异序列标签位点,以多重PCR法检测无精子症或严重少精子症患者的Y染色体微缺失情况.结果 180例无精子症或严重少精子症患者中共检出Y染色体微缺失15例,缺失率为8.3%.精液正常者(对照组)20例未发现Y染色体微缺失.9例Y染色体微缺失的无精子症患者睾丸细胞学检查均未发现精子.结论 Y染色体微缺失是造成男性精子发生障碍的常见病因之一.     

Klinefelter综合征患者Y染色体AZF微缺失分析

目的观察Klinefelter综合征患者Y染色体AZF微缺失发生情况。方法12例Klinefelter综合征患者ICSI/IVF等辅助受孕前进行睾丸细针穿刺吸液细胞学检查及Y染色体AZF微缺失分析。确定8个实验用序列标签位点（STS）,分别是：sY84、sY86、sY127、sY134、sY152、sY153、sY254、sY255,并以X/Y连锁锌指蛋白基因（ZFX/Y）为内对照进行多重PCR筛查AZF微缺失。结果睾丸细针穿刺吸液细胞学检查显示,3例（25.0%,3/12）可见到极少量形态较完整的精子及各级生精细胞、精子细胞,7例（58.3%,7/12）仅见少量生精细胞及精子细胞,2例（16.7%,2/12）仅见支持细胞,未见生精细胞及精子。12例Klinefelter综合征患者共检测出AZF微缺失2例分别为AZFa＋AZFc区缺失和AZFb＋AZFc区缺失;对照组32例样本未检出AZF基因微缺失。KS患者AZF微缺失检出率与对照组比较有显著差异（χ^2=5.587,P=0.018）。结论Klinefelter综合征患者存在Y染色体长臂AZF微缺失,缺失率为16.7%。     

Molecular analysis of microdeletions of the Y chromosome in Venezuelan males with idiopathic infertility

Today infertility is a major health problem affecting about 10-20% of couples. A male factor is assumed to be responsible in about 50% of the infertile couples. The origin of reduced testicular sperm function is unknown in about 60-70% of cases. There are several causes of male infertility such as varicocele, spermatic duct obstruction, and endocrine disorders. Micro-deletions in the Yq are known to represent the pathogenic mechanisms for infertile males. Three different non-overlapping regions designated as AZFa, AZFb, and AZFc are located in interval 5-6 of Yq, and are associated with impaired spermatogenesis in humans. To determine the prevalence of Y chromosomal microdeletions in Venezuelan males with idiopathic infertility, chromosomal, seminal, histological and molecular analyses were carried out in 29 Venezuelan males with idiopathic azoospermia or oligoospermia. Y-microdeletions analyses were performed using a multiplex polymerase chain reaction (PCR)-based technique with 22 sequences-tagged-sites (STSs). One of 29 patients (3.4%) had Yq microdeletions on AZFc. The frequency of AZF microdeletions in Venezuelan patients was similar to other populations with different ethnical or geographical origin.     

广州地区不育男性Y染色体无精子因子微缺失的筛查

目的探讨Y染色体无精子因子(azoospermia factor,AZF)区域微缺失与原发无精、严重少精症之间的关系。方法采用多重聚合酶链反应技术对广州地区103例原发无精子症、72例原发严重少精症患者及60名正常生育男性进行AZFa、AZFb、AZFc3个区域微缺失分析。结果60名正常生育男性未发现Y染色体AZF区域微缺失,175例生精障碍患者中发现AZF微缺失19例,总缺失率为10.9%。其中11例无精症患者和4例少精症患者的缺失发生在AZFc区域,缺失率为8.6%;1例无精症患者和2例少精症患者发生AZFb、AZFc双重缺失,缺失率为1.7%;1例无精症患者发生AZFa、b、c3个区域同时微缺失,缺失率0.6%。生精障碍组与正常生育男性组比较Y染色体AZF区域微缺失率差异具有统计学意义(P<0.01)。结论Y染色体AZF区域微缺失是引起男性无精、少精子症的重要原因之一,对原发无精、少精子症患者在单精子注射之前进行微缺失筛查是必要的。     

1011例男性不育患者Y染色体无精子症因子微缺失的筛查与临床表型分析

目的 探讨四川地区近6年不育男性Y染色体无精子症因子(azoospermia factor,AZF)微缺失的发生率、缺失类型及其与临床表型的关系.方法 应用多重PCR方法对713例非梗阻性无精症和298例重度少精症的男性进行Y染色体AZF微缺失分析.结果 AZF总体缺失率为10.48％ (106/1011),其中非梗阻性无精症患者缺失率为11.08％ (79/713),重度少精症患者缺失率为9.06％ (27/298).AZFa与AZFb完全缺失者均表现为无精症.AZFc缺失为最常见缺失类型且具有多种表型,占60.38％,其中37.50％的缺失者精液中有成熟精子.2例AZFb和1例AZFb-c部分缺失者精子密度呈轻度下降.结论 AZFc区是Y染色体AZF微缺失的缺失热点,AZFa或AZFb缺失者以及部分AZFc缺失者均表现为无精症.本研究进一步明确了AZF缺失基因型与表型的关系,证实Y染色体AZF微缺失检测对诊断男性不育具有重要的价值.     

Analysis of Yq microdeletions in infertile males by PCR and DNA hybridization techniques

Defects in spermatogenesis have been found associated with deletions of different portions of Y chromosome long arm (Yq), suggesting the presence of the azoospermia factor in the control of spermatogenesis. We studied 67 men with idiopathic azoospermia and severe oligozoospermia, cytogenetically normal, for the presence of microdeletions on Yq chromosome. By using polymerase chain reaction (PCR) and Southern blotting techniques we analysed the AZFa, AZFb and AZFc loci on Yq, where deletions have been associated with defects in spermatogenesis. Deletions of a portion of the Y chromosome were detected in five patients. Four of these patients shared deletions in distal Yq11 interval 6, including the DAZ gene, while one patient lacked loci in the proximal Yq11. Testicular histology of two patients bearing distal Yq11 deletions showed two different spermatogenic defects including Sertoli cell-only (SCO) syndrome and maturation arrest, while the patient with microdeletions in the proximal Yq11 showed a SCO phenotype.      

165例男性不育染色体核型及AZF基因缺失分析

目的探讨男性不育患者染色体核型异常及无精症因子（AZF）基因缺失与男性不育的关系。方法对2012年5月-2014年5月来本院就诊的（重庆地区）原发性男性不育患者165例,进行外周血G显带核型分析并采用多重PCR对无精症因子区域的15个标签序列位点进行检测。结果165例生精障碍患者中染色体异常共检出5例,1例为男性性反转（46,XX）,1例为克氏综合征（47,XXY）,1例为47,XY,＋mar,1例为46,XY,Y≥18,1例46,XY,in（9）,其余均为正常核型,总异常率为3.03％（5／165）;AZF基因位点发生微缺失患者共检出25例,总缺失率为15.15S。结论染色体异常和AZF微缺失是男性不育的重要原因,对男性不育诊断时有必要进行检查。     

桂西地区壮族不育患者Y染色体无精子因子筛查

目的探讨桂西地区壮族不育患者Y染色体无精子因子(azoospermia factor,AZF)微缺失与原发无精子、严重少精子症之间的关系。方法采用多重聚合酶链反应技术对桂西地区52例原发无精子症、76例原发严重少精子症患者及40名正常生育男性进行4个区域15个位点微缺失分析。结果 40名正常生育男性未发现Y染色体AZF微缺失,128例生精障碍患者中发现AZF微缺失13例,总缺失率为10.2%。生精障碍组与正常生育男性组比较Y染色体AZF微缺失率差异具有统计学意义(P0.01)。结论 Y染色体AZF微缺失是男性无精子、少精子症的要重原因之一。     

Screening for Y chromosome microdeletions in 226 Slovenian subfertile men.

BACKGROUND: The objective of this study was to estimate the frequency of Y chromosome microdeletions in the Slovenian population of infertile men and to analyse the consequences of mutation in respect to clinical severity and prognosis. METHODS: In a controlled clinical study at the university-based medical genetics service and infertility clinic, 226 infertile men undergoing ICSI were tested. The main outcome measures included polymerase chain reaction amplification of 16 genes and gene families and 42 sequence-tagged sites in the non-recombining region of the Y chromosome, semen, testicular volume and testicular histological analysis, serum FSH concentrations, fertilization and respective pregnancy rates. RESULTS: The incidence of deletions was 4.4%: 8.6% in men with azoospermia and 1.5% in men with oligoasthenoteratozoospermia. Isolated gene deletions were not identified. No statistically significant differences in clinical outcome measures were found in patients with mutations versus patients without mutations. High fertilization (49%) and pregnancy (43%) rates with sperm of patients with Y chromosome deletions were obtained. CONCLUSIONS: Testing for gene-specific microdeletions does not contribute significantly to the sensitivity of microdeletion test. Fertilization and pregnancy rates obtained using sperm of patients with Y chromosome deletions were comparable with those achieved in conventional IVF.     

Y染色体微缺失与男性不育的研究现状

男性不育患者中,Y染色体微缺失的比例占0．4％-55％,现已明确引起男性不育症的Y染色体微缺失已积累了一定数量,本文综述了Y染色体微缺失基因与男性不育的研究现状,为临床诊断、治疗男性不育症提供理论依据。