Genetic Screening for Chromosomal Abnormalities and Y Chromosome Microdeletions in 846 Infertile Korean Men

BACKGROUND: Chromosomal abnormalities are confirmed as one of the frequent causes of male infertility. The microdeletion of the azoospermia factor (AZF) region in the Y chromosome was discovered as another frequent genetic cause associated with male infertility. The aim of this study was to evaluate the frequency and type of chromosomal abnormalities and Y chromosome microdeletions in Korean infertile men. METHODS: A total of 846 infertile men with azoospermia and severe oligozoospermia were included for genetic screening. Cytogenetic analyses using G-banding and screening for Y chromosome microdeletions by multiplex PCR for AZF genes were performed. RESULTS: Chromosomal abnormalities were detected in 112 infertile men (13.2%). Of these, Klinefelter's syndrome was the most common (55.4%, 62/112), followed by balanced translocation including translocation between sex chromosome and autosome (14.3%), Yq deletion (13.4%), X/XY mosaicism with Yq deletion (12.5%), and XX male (4.5%). The overall prevalence of Y chromosome microdeletions was 9.2% (78/846). Most microdeletions were in the AZFc region (51.3%) with a low incidence in AZFa (7.7 %) and AZFb (6.4 %). Combined deletions involving the AZFbc and AZFabc regions were detected in 26.9 % and 7.7 % of men, respectively. Among the infertile men with Y chromosome microdeletions, the incidence of chromosomal abnormality was 25.6% (20/78). CONCLUSIONS: There was a high incidence (20.1%) of chromosomal abnormalities and Y chromosome microdeletions in Korean infertile men. These findings strongly suggest that genetic screening for chromosomal abnormalities and Y chromosome microdeletions should be performed, and genetic counseling should be provided before starting assisted reproductive techniques.

Y Chromosome Microdeletions and Partial AZFc Deletions in Infertile Men from South India.

Aim: Yq microdeletions involving the azoospermia factor (AZF) region are the second most frequent genetic cause of spermatogenic failure next to Klinefelter syndrome. These deletions occur in about 10-15 percent of men with azoospermia and severe oligozoospermia. Molecular screening for AZF deletions has become mandatory in the work-up of infertile men. Further, partial AZFc deletions categorized as gr/gr, b2/b3, b1/b3 and b2/b4 deletions have also been known to affect spermatogenesis. This study aimed to screen for both classical AZF deletions in 250 karyotypically normal infertile men from south India and partial AZFc deletions as a case-control analysis involving 108 fertile men. Methods: PCR amplification involving two multiplex reactions was carried out using primers for six STSs sY84, sY86 (AZFa), sY127, sY134 (AZFb), and sY254, sY255 (AZFc) with two internal controls (SRY, ZFY). Further, those men who showed deletions with one or both STSs sY1291 and sY1191 were subsequently tested with sY1189 and sY1192 to detect partial AZFc deletions. Results: One individual showed deletion of all the three AZF regions while two men had only AZFc deletion. Deletion of partial AZFb (sY127) was seen besides complete AZFc region in the fourth patient. The gr/gr, b2/b3 and b1/b3 deletions were detected in 24 (9.6%), one (0.4%) and nine (3.6%) infertile men in comparison with five, one and two fertile men respectively. The b2/b4 deletion was observed in a single azoospermic individual. Conclusion: Screening for AZF deletions would help in not only determining the cause for male infertility but also in its management and accurate genetic counselling.

Pedigree analysis on the relationship between small Y and azoospermia factor microdeletion / 中华泌尿外科杂志

Objective To study the relationship between small Y and azoospermia factor (AZF)microdeletions and the effect on male infertility.Methods Data of 379 infertile males of chromosomal karyotype analysis from May 2010 to October 2011 were investigated.Patients with small Y chromosome were also performed C banding and AZF microdeletions,and their fathers and brothers were offered the same examinations.Results Eight patients were small Y chromosome,and their fathers or brothers' chromosome karyotypes were consistent with the probands.Among the 8 cases,there were 3 patients with AZF microdeletions,while their fathers and brothers didn't have microdeletions.Another 5 cases of small Y and their fathers did not exist AZF microdeletions.Conclusions The small Y karyotype is not the key factors that cause male infertility.The reason for infertile patients with small Y and AZF microdeletions was maybe the microdeletions.However,patients with small Y but without AZF microdeletions are not important to male infertility.

High prevalence of AZFb microdeletion in Iranian patients with idiopathic non-obstructive azoospermia.

Background & objectives: Genetic factors contribute about 10 per cent of male infertility. Among these, genes in azoospermia factor (AZF) region including AZFa, AZFb, AZFc and AZFd on the long arm of Y chromosome are considered most important for spermatogenesis. Deletions in these regions are thought to be involved in some cases of male infertility associated with azoospermia or oligozoospermia. We studied the incidence of AZF deletions among Iranian infertile men with idiopathic non-obstructive azoospermia. Methods: A total of 100 Iranian azoospermic infertile men were selected for the molecular study of Y chromosome microdeletions. The presence of 13 sequence tagged site (STS) markers from AZF region was investigated using multiplex polymerase chain reaction (M-PCR). One hundred fertile men were also studied as control group. Results: Twelve (12%) patients showed Y chromosome microdeletions and among these, deletion in AZFb region was the most frequent (66.67%) followed by AZFc (41.67%), AZFd (33.33%) and AZFa (8.33%), respectively. Interpretation & conclusions: Because of relatively high incidence of Y chromosome microdeletions among Iranian azoospermic patients, molecular screening may be advised to infertile men before using assisted reproductive treatments.

Y chromosome microdeletions in Brazilian fertility clinic patients

Microdeletions in Yq are associated with defects in spermatogenesis, while those in the AZF region are considered critical for germ cell development. We examined microdeletions in the Y chromosomes of patients attended at the Laboratory of Human Reproduction of the Clinical Hospital of the Federal University of Goiás as part of a screening of patients who plan to undergo assisted reproduction. Analysis was made of the AZF region of the Y chromosome in men who had altered spermograms to detect possible microdeletions in Yq. Twenty-three patients with azoospermia and 40 with severe oligozoospermia were analyzed by PCR for the detection of six sequence-tagged sites: sY84 and sY86 for AZFa, sY127 and sY134 for AZFb, and sY254 and sY255 for AZFc. Microdeletions were detected in 28 patients, including 10 azoospermics and 18 severe oligozoospermics. The patients with azoospermia had 43.4% of their microdeletions in the AZFa region, 8.6% in the AZFb region and 17.4% in the AZFc region. In the severe oligozoospermics, 40% were in the AZFa region, 5% in the AZFb region and 5% in the AZFc region. We conclude that microdeletions can be the cause of idiopathic male infertility, supporting conclusions from previous studies.

Y chromosome microdeletions in Turkish infertile men.

AIMS: To detect the frequency and types of both chromosomal abnormalities and Y chromosome microdeletions in infertile men attending to our university intracytoplasmic sperm injection ICSI/IVF centre and fertile control subjects in our patient population. SETTINGS AND DESIGN: A total of 50 infertile men who were referred to IVF center of Meram medical faculty were selected for the molecular azospermia factor (AZF) screening program. MATERIALS AND METHODS: Karyotype analysis and polymerase chain reaction amplification using 15 Y-specific sequence-tagged sites of AZF region were done. RESULTS: The total prevalence of chromosomal abnormalities was found to be 10% (5/50), including 4 patients with numerical and 1 patient with structural abnormalities. Overall, 4 of the 50 patients tested (8%) exhibited deletions of the Y chromosome, 3 of them being azospermic and 1 of them oligospermic men. The frequency of the microdeletions in subgroups with azospermia and oligozoospermia was found to be 10.7% (3/29) and 4.7% (1/21) respectively. Microdeletions of AZFb and AZFc regions were detected in all of the 4 patients. Neither AZFa nor AZFd microdeletions were indicated. CONCLUSIONS: Our findings suggest that one must know whether there is a genetic cause for male infertility before patients can be subjected to ISCI or testicular sperm extraction (TESE)/ISCI treatment.

Correlation among unexplained oligospermatism,azoospermatism and micro-deletion in AZF gene / 基础医学与临床

Objective To investigate the association among oligospermatism,azoospermatism in male sterility patients and micro-deletion in AZF gene of Y chromosome and to establish a integrate clinical diagnostic method for screening micro-deletion in AZF gene in Chinese.Methods PCR method was used to detect micro-deletion in AZF gene in 62 oligospermatism and azoospermatism patients and 20 normal male controls.Results 13.64%(6/44) of oligospermatism patients and 22.22%(4/18) of azoospermatism patients presented micro-deletion.However,micro-deletion was not found in 20 normal male controls.Furthermore,micro-deletion occur mostly in AZFc region.Conclusion Micro-deletion of AZF gene from Y chromosome is one of the major risks for oligospermatism and azoospermatism.

Relationship between Microdeletions on the Y Chromosome and Defect of Spermatogenesis / 대한불임학회지

OBJECTIVES: To estimate the frequency of Y chromosome microdeletions in the Korean population of infertile men and to evaluate the relationship between microdeletion on the Y chromosome and clinical phenotypes of infertile men with idiopathic azoospermia and oligozoospermia. MATERIALS AND METHODS: Genomic DNA was extracted from blood samples collected from 330 infertile men attending the Infertility Clinic at Samsung Cheil Hospital, Korea. Six sequence tagged sites (STSs) spanning the azoospermia factor (AZF) regions of the Y chromosome were amplified by polymerase chain reactions (PCRs). RESULTS: Microdeletions on Y chromosome were detected in 35 (10.6%) of the 330 infertile men. Most of the microdeletions (91.4%) involved AZFb or AZFc. The high incidence of microdeletions were found in AZFc region (57.1%), but the low in AZFa (8.6%) and AZFb (5.7%). Larger microdeletions involving two or three AZF regions were detected in 28.6% of cases. All patients (6 patients) with deletion of AZFa region showed no germ cell phenotypes, Sertoli cell only syndrome or Leydig cell hyperplasia in histopathologic examinations. CONCLUSION: Microdeletions on the Y chromosome, especially, at AZFc/DAZ regions may be the major cause of azoospermia and severe oligozoospermia. We suggest that idiopathic infertile men have genetic counselling and microdeletion analysis on the Y chromosome before IVF-ET and ART program.

Relationship between Microdeletions on the Y Chromosome and Defect of Spermatogenesis / 대한불임학회지

OBJECTIVES: To estimate the frequency of Y chromosome microdeletions in the Korean population of infertile men and to evaluate the relationship between microdeletion on the Y chromosome and clinical phenotypes of infertile men with idiopathic azoospermia and oligozoospermia. MATERIALS AND METHODS: Genomic DNA was extracted from blood samples collected from 330 infertile men attending the Infertility Clinic at Samsung Cheil Hospital, Korea. Six sequence tagged sites (STSs) spanning the azoospermia factor (AZF) regions of the Y chromosome were amplified by polymerase chain reactions (PCRs). RESULTS: Microdeletions on Y chromosome were detected in 35 (10.6%) of the 330 infertile men. Most of the microdeletions (91.4%) involved AZFb or AZFc. The high incidence of microdeletions were found in AZFc region (57.1%), but the low in AZFa (8.6%) and AZFb (5.7%). Larger microdeletions involving two or three AZF regions were detected in 28.6% of cases. All patients (6 patients) with deletion of AZFa region showed no germ cell phenotypes, Sertoli cell only syndrome or Leydig cell hyperplasia in histopathologic examinations. CONCLUSION: Microdeletions on the Y chromosome, especially, at AZFc/DAZ regions may be the major cause of azoospermia and severe oligozoospermia. We suggest that idiopathic infertile men have genetic counselling and microdeletion analysis on the Y chromosome before IVF-ET and ART program.

Screening for microdeletions of AZF region of Y chromosome in patients with spermatogenetic malfunction and its significance / 中华泌尿外科杂志

Objective To investigate the condition of microdeletions of AZF region of the Y chromosome in Chinese patients with spermatogenetic malfunction. Methods Six Y chromosome specific sequence-tagged-sites(STS) in AZF region were screened and the microdeletions were determined by PCR in 27 patients with spermatogenetic malfunction. Results Microdeletions in genomic DNA were observed in 2 cases who presented with azoospermia and limited to AZFc subregion.The total deletion rate was 7.4%.The deletion patterns of the 2 cases were DAZ(sY254,sY255) and DAZ plus sY157,respectively. Conclusions Like other races, microdeletions of the Y chromosome in Chinese people may be one of the causes of spermatogenetic malfunction.Therefore prior to assistant reproduction,screening for microdeletions of the Y chromosome in patients with spermatogenetic malfunction is necessary.