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）

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.

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.

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.

Molecular genetic analysis of microdeletion on AZF/DAZ gene in patients with idiopathic azoospermia and severe oligozoospermia in Fujian

Objective: To identify microdeletions in azoospermia factor(AZF) gene loci in patients with idiopathic azoospermia and severe oligozoospermia in Fujian. Methods: Molecular genetic detection method was used to detect microdeletion at the AZFa, AZFb, AZFc /DAZ,SRY region of Y chromosome in 47 azoospermia and 4 severe oligozoospermia patients. Genomic DNA was extracted from peripheral blood. The sequence tagged site (STS) primers tested in each cases were sY84(AZFa), sY 143(AZFb) sY254(AZFc).SRY region of Y chromosome for control. The PCR products were analyzed on a 2.0% agarose gel. Results: Microdeletions of the Y-chromosomal AZF loci were revealed in 18(35.3%,18/51) of 51 patients with idiopathic azoospermia and severe oligozoospermia. AZFa deletion was found in four (7.8%) patients, AZF b in five (9.8%) patients, AZF c in four (7.8%) patients. AZF a+b in one(1.9%)patient, AZF b+c in two (3.9%) patients, AZF a+b+c in two (3.9%)patients respectively. No deletion of SRY region was found. No deletion of AZF a, AZF b, AZF c/DAZ,SRY regions was found in five fertile male who had at least one or more children. Conclusions: Microdeletions on AZF/DAZ gene loci were major genetics defects leading to azoospermia and severe oligozoospermia in male idiopathic infertility in Fujian. It is necessary to have genetic counseling and carry out microdeletion detection on AZF/DAZ gene loci before performing intracytoplasmic sperm injection (ICSI).

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）

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.

Y-chromosome microdeletions in nonobstructive azoospermia and severe oligozoospermia

The aim of the present work was to present the outcomes of the patients with Y-chromosome microdeletions treated by intracytoplasmic sperm injection （ICSI）, either using fresh （TESE） or frozen-thawed （TESE-C） testicular sperm and ejaculated sperm （EJAC）. The originality of this work resides in the comparisons between the different types of Y-microdeletions （AZFa, AZFb, and AZFc） and treatments, with detailed demographic, stimulation, embryological, clinical, and newborn （NB） outcomes. Of 125 patients with Y-microdeletions, 33 patients presented severe oligozoospermia （18 performed ICSI with ejaculated sperm） and 92 secretory azoospermia （65 went for TESE with 40 having successful sperm retrieval and performed ICSI）. There were 51 TESE treatment cycles and 43 TESE-C treatment cycles, with a birth of 19 NB （2 in AZFa/TESE-C, 12 in AZFc/TESE, and 5 in AZFc/TESE-C）. Of the 29 EJAC cycles, there was a birth of 8 NB （in AZFc）. In TESE and EJAC cycles, there were no significant differences in embryological and clinical parameters. In TESE-C cycles, there was a significant lower oocyte maturity rate, embryo cleavage rate and mean number of embryos transferred in AZFb, and a higher mean number of oocytes and lower fertilization rate in AZFc. In conclusion, although patients with AZFc microdeletions presented a high testicular sperm recovery rate and acceptable clinical outcomes, cases with AZFa and AZFb microdeletions presented a poor prognosis. Due to the reported heredity of microdeletions, patients should be informed about the infertile consequences on NB and the possibility of using preimplantation genetic diagnosis for female sex selection.

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。

针对Y染色体微缺失检测两种不同方案的比较

目的:比较两种Y染色体微缺失检测方案的结果。方法:采用荧光定量PCR方法对方案一(六位点法:sY84,sY86,sY127,sY134,sY254,sY255)和方案二(八位点法:sY84,sY86,sY127,sY134,sY254,sY255,sY145,sY152)的检测结果进行比较。结果:六位点法AZF区的缺失检出率为9.34%(575/6177),八位点法AZF区的缺失检出率为8.85%(542/6122),两种方法AZF区的缺失检出率没有显著差异。结论:虽然八位点法增加对AZFd区域位点的检测,但缺失检出率与六位点法无差异。因此,从实验操作、经济成本及对临床策略指导等方面考虑,Y染色体微缺失检测六位点法优于八位点法。

Ion Torrent PGM测序在87例无精子症Y染色体微缺失分析中的应用

目的:探究Ion Torrent PGM测序技术在Y染色体微缺失检测中的可行性。方法:收集非梗阻性无精子症患者87例作为实验对象,全部完成精液常规、生殖激素和染色体核型分析。以多重PCR法作为对照,用Ion Torrent PGM测序技术检测Y染色体微缺失,比较两种方法的检出率。结果:PGM测序法检出率为49.4%,多重PCR法检出率为12.6%,Ion Torrent PGM的检出率明显高于多重PCR,Ion Torrent PGM检出的AZF缺失患者包含全部多重PCR检出患者,且缺失位点完全一致。同时,在87例男性不育患者中,Ion Torrent PGM检出24例,共14种男性不育相关基因突变,总阳性率为27.59%。结论:对无精子症患者,采用Ion Torrent PGM测序检测AZF缺失,可明显提高检出率;同时PGM测序法可以检出更多的男性不育相关基因突变位点,为无精子症的诊断提供帮助。

不育男性无精子症因子微缺失的分子与临床特征:5年研究回顾

目的:近年来,Y染色体长臂无精子症因子(AZF)微缺失与男性不育关系的研究已经取得了很大的进展。然而,AZF微缺失的形成机理及各种缺失类型与临床表型之间的关系还不十分确定。本研究的目的是探讨中国不育男性的Y染色体微缺失的发生率、缺失类型以及基因型与表型之间的关系。方法:本研究对2005年至2009年本院男科门诊502例非梗阻性无精子症和306例严重少精子症的不育男性进行Y染色体AZF缺失分析。结果:AZF总体缺失率为7.80%(63/808),其中无精子症不育男性缺失率为9.16%(46/502),严重少精症患者为5.56%(17/306)。完全的AZFa缺失或AZFb缺失患者的精液中均没有成熟精子,而AZFc缺失的表型是多样化的。1例部分AZFb缺失患者有成熟精子发生,精子密度呈轻度进行下降。最常见的缺失类型为AZFc b2/b4亚型,占60.32%(38/63),其中39.47%(15/38)的患者精液中能发现成熟精子,其中1例为自然遗传的AZFc b2/b4缺失。63例缺失患者中仅1例AZFc b2/b4缺失患者的精子密度超过2×109/L。结论:AZF微缺失对精子发生障碍具有良好的诊断和评估价值。对Y染色体微缺失的大样本临床研究有利于进一步明确基因型与表型的关系,更好地理解AZF缺失的机制。

改良多重聚合酶链反应检测Y染色体AZF微缺失

目的:对多重聚合酶链反应(PCR)优化改良,检测Y染色体无精子因子(AZF)区域微缺失。方法:实验组选择160例精子发生障碍患者,对照组90例为合格捐精者。按照欧洲男科协会和欧洲分子遗传实验质控网检测指南进行多重PCR,对Y染色体序列标签点引物序列和PCR反应条件优化改良,筛查AZFa、b、c区域的微缺失。结果:采用改良多重PCR,160例生精障碍患者中发现AZF微缺失14例(8.75%),其中AZFc12例,AZFa+b+c1例,AZFb+c1例;对照组90例未发现微缺失;两组比较,差异有极显著性(P<0.001)。所有PCR产物电泳条带清晰,时间缩短至1h。结论:对欧洲男科协会和欧洲分子遗传实验质控网推荐的多重PCR技术优化改良,用于精子发生障碍患者的YqAZF区域筛查,结果可靠、快捷、重复性好。

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。

Y染色体基因微缺失与男性不育的关系

目的 :探讨男性不育患者尤其是特发性无精子症、严重少精子症及双侧输精管缺如与 Y染色体基因 (无精子因子 ,AZF)微缺失的关系。方法 :对 97例男性不育患者及 2 0例正常男性采用多重聚合酶链反应法进行基因微缺失检测。结果 :36例特发性无精症患者中存在 3例缺失 ,占 8.33% ;1 4例双侧输精管缺如患者存在 2例缺失 ,占 1 4.2 9% ;2 7例严重少精症患者中存在 2例缺失 ,占 7.41 %。2 0例精子数正常的男性不育患者及 2 0例正常男性对照无 AZF缺失。缺失以 AZFa,AZFc区为主 ,AZFb区无缺失。结论 :Y染色体 AZF微缺失可能是导致男性特发性无精症、少精症的原因之一 ,双侧输精管缺如患者也存在

Y染色体微缺失与精子发生的相关性分析

目的:探讨Y染色体AZF微缺失与男性精子发生之间的关系。方法:采用聚合酶链反应技术对343例无精子症(包括精子发生基本正常177例和生精障碍166例)、633例严重少精症、45例严重弱精症患者进行AZFa、AZFb、AZFc等3个区域微缺失分析。结果:166例生精障碍患者中发现AZF微缺失41例,总缺失率为24.7%;177例生精基本正常的男性发现3例合并AZFc的微缺失,缺失率为1.7%;在严重少精组发现AZF微缺失49例,总缺失率为7.7%;弱精症患者无一例发现AZF微缺失。生精障碍组与其他男性比较Y染色体AZF区域微缺失率差异有统计学意义(P<0.01)。结论:Y染色体AZF区域微缺失与男性生精障碍有着明显的相关性,因此有必要对门诊的生精障碍患者以及准备行辅助生育技术的生精障碍患者行Y染色体AZF微缺失筛查。对于这些患者是否需要进行PGD技术还需要更多的数据证明。

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。

安徽地区1163例男性不育患者Y染色体无精子因子基因微缺失分析

目的通过分析安徽地区1 163例不育男性的Y染色体无精子因子(AZF)微缺失情况及特点,探讨其在诊治男性不育症中的临床价值。方法采用多重聚合酶链式反应(m PCR)技术扩增1 163例精子数目、活力异常的男性不育患者AZF基因的15个序列标签位点(STS),并使用琼脂糖凝胶电泳对目的片段进行鉴别分析。结果 1 163例不育患者中130例(11.18%)患者AZF基因位点发生微缺失。在AZF微缺失组合类型中,AZFc+AZFd位点微缺失最多,共97例(8.34%,97/1 163);其次为AZFb+AZFc+AZFd的组合缺失,共21例(1.81%,21/1 163);AZFa+AZFb+AZFc+AZFd四个AZF区域均发生缺失的患者,以及仅仅在AZFa区域发生微缺失的患者分别为6例,各占总不育患者的0.52%(6/1 163)。结论 Y染色体AZF区域微缺失是部分男性不育症的重要遗传致病因素,有必要对精液质量异常的男性不育患者进行AZF基因微缺失检测,将有助于明确病因并指导后续治疗。

唐氏综合征高危孕妇血浆中游离胎儿DNA的Y染色体微缺失筛查

目的利用孕妇血浆中游离胎儿DNA在孕早期进行Y染色体微缺失筛查，诊断男性胎儿无精子症因子（AZF）缺失情况。方法留取2013年6月～2014年8月参加产前检测的16～34孕周唐氏综合征筛查高危孕妇的外周血标本89例，提取出全血基因组DNA后利用Y染色体微缺失检测试剂盒检测AZF微缺失。结果86例孕妇妊娠至胎儿出生，其中男胎孕妇45例，女胎孕妇41例。妊娠女性胎儿的孕妇血浆DNA仅扩增出ZFX／ZFY对照基因，而妊娠男性胎儿的孕妇血浆DNA同时扩增出SRY，ZFX／ZFY对照基因，且有3例样本检测出AZF基因微缺失。结论通过提取孕妇血浆中游离胎儿DNA能够检测出胎儿是否伴有AZF基因微缺失，从而提前预测胎儿今后罹患生精障碍的风险。