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1.
Oestrogen Receptor β (ERβ) gene plays an important role in the regulation of fertility in both males and females. Polymorphism in CA repeat located in the flanking region of ERβ has been shown to be associated with several diseases, but its association with male infertility has not been analysed so far. However, Rsa I polymorphism (rs1256049) in exon 5 of ERβ has been shown to be associated with male infertility in Caucasian patients. Hence, we have analysed 695 Indian men, including 443 infertile and 252 fertile men to evaluate the association of CA repeat length and Rsa I polymorphisms in male infertility. Our results revealed no significant difference in the distribution of CA repeat length between infertile (mean ± SD 23.24 ± 2.06, median 24) and fertile men (mean ± SD 23.16 ± 2.27, median 24). The analysis of dosage effect by classifying samples into SS (short/short), SL (short/long) and LL (long/long) groups also did not show any significant difference between infertile and fertile men. Similarly, Rsa I polymorphism also did not show any significant difference between infertile and fertile men. Furthermore, the combined analysis of CA repeat and Rsa I polymorphisms by haplotyping showed that the distribution of haplotypes was not significantly different between fertile and infertile men. Our results suggest that CA repeat length and Rsa I polymorphisms in ERβ are not associated with infertility in Indian men.  相似文献   

2.
Androgens, acting through the androgen receptor (AR), play a role in secondary sexual differentiation from the prenatal stage to adulthood, including spermatogenesis. The AR gene has 2 polymorphic trinucleotide repeats (CAG and GGN) in exon 1. The CAG repeat length polymorphism has been well studied in a variety of medical conditions, including male infertility. Many of these studies have shown an association of the expanded CAG repeats with male infertility, although this is not true for all populations. The GGN repeat, in contrast, has been less thoroughly studied. Thus far, only 4 reports worldwide have analyzed the GGN repeat, alone or in combination with the CAG repeat, in male infertility cases. No such study has been undertaken on infertile Indian men. Therefore, we have analyzed AR-GGN repeats in a total of 595 Indian males, including 277 azoospemric, 97 oligozoospermic, and 21 oligoteratozoospermic cases, along with 200 normozoospermic controls. The analysis revealed no difference in the mean number or the range of the repeat between cases (mean = 21.51 repeats, range 15-26 repeats) and controls (mean 21.58 repeats, range 15-26 repeats). Furthermore, no difference was observed when azoospermic (mean = 21.53 repeats, range 15-26 repeats), oligozoospermic (mean = 21.46 repeats, range 15-26 repeats), and oligoteratozoospermic cases (mean = 21.48, range 19-26 repeats) were compared individually with the controls.  相似文献   

3.
Androgens are essential for spermatogenesis. It has been postulated that androgen activity is modulated directly or indirectly by genetic variability in the androgen receptor gene sequence, including CAG/GGN polymorphisms and single-nucleotide polymorphisms (SNP). In this study, the frequency of 6 SNPs that constitute a haplotype in the androgen receptor sequence was determined by enzyme restriction assays and allele-specific polymerase chain reactions in 117 secretory azo/oligozoospermic men (93 idiopathic and 24 excryptorchidic), and in 121 controls with normal spermatogenesis (42 obstructive and 79 normozoospermic men) whose hormonal measurements and length of CAG/GGN polymorphisms were previously determined. The frequency of these 6 SNPs was not different between patients and controls. A total of 10 haplotypes (HAPs 1-10) formed by these 6 SNPs were found, and one of these haplotypes was observed with high frequency in the total population (HAP1, 83.2%; P < .001, χ(2) test). The frequency of the 10 haplotypes was not different between patients and controls, except for HAP5, which was only detected in one patient with a history of bilateral cryptorchidism (P = 0.014, Bonferroni test). On the other hand, no associations were found between the haplotypes studied and shorter or longer CAG or GGN polymorphisms. Interestingly, we found that the CAG 21 allele, which was previously correlated with an increased risk of idiopathic spermatogenic impairment, was more frequently found among the less common haplotypes that have higher follicle-stimulating hormone serum levels. In summary, we did not find an increased frequency of particular haplotypes in infertile men with idiopathic spermatogenic impairment compared with control men; however, we found that the CAG 21 allele, which appears to be associated with male infertility, is observed at a significantly higher proportion among the less common androgen receptor haplotypes.  相似文献   

4.
雄激素受体基因CAG重复多态性与男性不育关系的Meta分析   总被引:1,自引:1,他引:0  
目的:采用Meta分析系统评价雄激素受体(AR)基因CAG串联重复多态性与男性不育的关系。方法:检索Medline、CBM等数据库中有关AR基因CAG重复数与男性不育相关性的病例对照研究,并用RevMan4.2软件进行统计分析。结果:共纳入32篇符合条件的文献,累计特发性不育病例3153例、对照2314例。数据合并结果显示,男性不育、无精子症及中度少精子症者其CAG重复数均数均显著高于对照人群(P<0.01),三者与对照间CAG重复数均数的标准均数差分别为0.27,95%CI:0.17~0.37;0.29,95%CI:0.08~0.50;0.27,95%CI:0.13~0.41。而且,敏感性分析结果也与以上研究结果一致。结论:AR基因CAG重复多态性其重复数增多与精子发生障碍的风险相关。  相似文献   

5.
The CAG repeat and its association with infertility has been debatable. Therefore, this study was planned to assess the distribution of CAG repeat expansion in Egyptian patients and to investigate its association with male infertility. Forty-five infertile men were eligible for the study in addition to 20 aged-matched fertile males as control. Semen analysis, scrotal sonography, assay of serum testosterone, follicle-stimulating hormone (FSH) and luteinising hormone (LH), and determination of the CAG repeat number within exon 1 of the androgen receptor (AR) gene were carried out. Statistically significant difference was found between infertile and control groups regarding sperm count, sperm motility, serum FSH level and CAG repeats (P < 0.05); statistically insignificant difference for the CAG repeats (P = 1.0) was found between oligozoospermic and asthenospermic groups; negative correlation was found between CAG repeat length and sperm count, and a positive correlation was found between CAG repeat length and serum FSH (P < 0.05). Our results validate the concept that long stretches of CAG repeat may be associated with lower AR function with derangement of sperm production, and this may contribute to male infertility in Egyptian men.  相似文献   

6.
Androgen receptor (AR) CAG(n) (polyglutamine) and GGN(n) (polyglycine) repeat polymorphisms determine part of the androgenic effect and may influence adiposity. The association of fat mass, and its regional distribution, with the AR CAG(n) and GGN(n) polymorphisms was studied in 319 and 78 physically active nonsmoker men and women (mean ± SD: 28.3 ± 7.6 and 24.8 ± 6.2 years old, respectively). The length of CAG and GGN repeats was determined by polymerase chain reaction and fragment analysis, and confirmed by DNA sequencing of selected samples. Men were grouped as CAG short (CAG(S)) if harboring repeat lengths ≤ 21, the rest as CAG long (CAG(L)). The corresponding cutoff CAG number for women was 22. GGN was considered short (GGN(S)) if GGN ≤ 23, the rest as GGN long (GGN(L)). No association between AR polymorphisms and adiposity or the hormonal variables was observed in men. Neither was there a difference in the studied variables between men harboring CAG(L) + GGN(L),CAG(S) + GGN(S),CAG(S) + GGN(L), and CAG(L) + GGN(S) combinations. However, in women, GGN(n) was linearly related to the percentage of body fat (r = 0.30, P < .05), the percentage of fat in the trunk (r = 0.28, P < .05), serum leptin concentration (r = 0.40, P < .05), and serum osteocalcin concentration (r = 0.32, P < .05). In men, free testosterone was inversely associated with adiposity and serum leptin concentration, and positively with osteocalcin, even after accounting for differences in CAG(n), GGN(n), or both. In summary, this study shows that the AR repeat polymorphism has little influence on absolute and relative fat mass or its regional distribution in physically active men. In young women, GGN length is positively associated with adiposity, leptin, and osteocalcin.  相似文献   

7.
To evaluate the association between neutral α-glucosidase (NAG) activity and sperm DNA fragmentation (DFI), ejaculates from 24 men undergoing evaluation for sperm DNA damage as a part of infertility assessment were analysed. The mean ± SD and range for the semen quality of the 24 ejaculates are as follows: volume (3.1 ± 1.3, 1.8–6.0 ml); sperm concentration (45.6 ± 41.1, 1.3–151.2 × 106 ml−1); sperm motility (52.8 ± 28.8, 1–95%); sperm with fragmented DNA (17.6 ± 15.4, 1.7–56.0%); sperm with immature chromatin (9.6 ± 3.8, 2.5–19.1%); NAG activity (37.9 ± 18.3, 4.4–75.3 mU ml−1). The only sperm parameter significantly correlated with neutral α-glucosidase is the percentage of sperm DFI [correlation coefficient ( r ) = 0.4376, P  = 0.03].  相似文献   

8.
The genetic basis of male infertility remains unclear in the majority of cases. Recent studies have indicated an association between microdeletions of the azoospermia factor a (AZFa)-AZFc regions of Yq and severe oligospermia or azoospermia. Increased (CAG)n repeat lengths in the androgen receptor (AR) gene have also been reported in infertile men. Therefore, in order to assess the prevalence of these genetic defects to male infertility, 183 men with non-obstructive azoospermia (n = 70), obstructive azoospermia (n = 33), severe oligospermia (n = 80) and 59 fertile men were examined cytogenetically and at molecular level for Yq deletions, microdeletions, and AR-CAG repeat lengths along with hormonal profiles [luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T)]. We used high resolution cytogenetics to detect chromosome deletions and multiplex polymerase chain reaction (PCR) involving 27 sequence-tagged site (STS) markers on Yq to determine the rate and extent of Yq microdeletions. PCR amplification with primers flanking exon 1 of AR gene was used to determine the AR-(CAG)n repeat lengths. Hormonal profiles (LH, FSH and T levels) were also analysed in infertile and fertile men. Testicular biopsies showed Sertoli cell only (SCO) morphology, maturation arrests (MA) and hypospermatogenesis. No chromosome aberrations were found in infertile men but there was a significant increase (p < 0.001) in the association of acrocentric chromosomes including the Y chromosome. Yq microdeletions were found in 16 non-obstructive azoospermic men (16 of 70; 22%) and seven severe oligospermic individuals (seven of 80; 8.7%) and most of them had deletions in the sY240 locus. No Yq microdeletions were detected in patients with obstructive azoospermia. No statistically significant difference in the mean length of CAG repeats in AR gene was observed between infertile and fertile men (22.2 +/- 1.5 and 21.5 +/- 1.4 respectively). No significant increase or decrease in levels of LH, FSH and T was observed in infertile and fertile men. In some infertile men, significantly elevated levels of FSH alone or in combination with LH were found to be indicative of failure of spermatogenesis and/or suggestive of testicular failure. Y-chromosome microdeletions contribute to infertility in some patients but no relationship could be established with the (CAG)n repeat lengths in exon 1 of the AR gene in infertile Indian men.  相似文献   

9.
AIM: To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syndrome (AIS) phenotype. METHODS: We analyzed lengths of androgen receptor (AR)-CAG and GGN repeats in 69 AIS cases, along with 136 unrelated normal male individuals. The lengths of repeats were analyzed using polymerase chain reaction (PCR) amplification followed by allelic genotyping to determine allele length. RESULTS: Our study revealed significantly shorter mean lengths of CAG repeats in patients (mean 18.25 repeats, range 14-26 repeats) in comparison to the controls (mean 22.57 repeats, range 12-39 repeats) (two-tailed P < 0.0001). GGN repeats, however, did not differ significantly between patients (mean 21.48 repeats) and controls (mean 21.21 repeats) (two-tailed P = 0.474). Among patients' groups, the mean number of CAG repeats in partial androgen insensitivity cases (mean 15.83 repeats) was significantly less than in complete androgen insensitivity cases (mean 19.46 repeats) (two-tailed P < 0.0001). CONCLUSION: The findings suggest that shorter lengths of repeats in the AR gene might act as low penetrance genetic background in varying manifestation of androgen insensitivity.  相似文献   

10.
The roles of androgen receptor AR(CAG)n gene polymorphisms and sex hormone-binding globulin SHBG(TAAAA)n gene polymorphisms on semen quality were studied. One hundred fourteen men were included in the study: 85 with normal sperm count and 29 oligospermic. The genotype analysis, on DNA extracted from spermatozoa, revealed five SHBG(TAAAA)n alleles with 6–10 repeats and 18 AR(CAG)n alleles with 12–32 repeats. The SHBG allelic distribution showed that in men with normal sperm count and motility, those with short SHBG alleles had higher sperm concentration than men with long SHBG alleles ( P  = 0.039). As concerns AR(CAG)n polymorphisms, men with short AR alleles had lower sperm motility compared to those with long AR alleles ( P  < 0.001) in both total study population and normal sperm count men. The synergistic effect analysis of the two polymorphisms revealed an association between sperm motility ( P  = 0.036), because of the effect of AR(CAG)n polymorphism on sperm motility. In conclusion, long AR alleles were found to be associated with higher sperm motility, while short SHBG alleles were associated with higher sperm concentration, supporting the significance of these genes in spermatogenesis and semen quality.  相似文献   

11.
BACKGROUND: Genetic susceptibility may explain some familial clusters of prostate cancer. The polymorphic androgen receptor (AR) gene, which mediates androgen activity in the prostate, is a candidate gene that may influence predisposition to the disease. METHODS: We analyzed the polymorphic (CAG)n and (GGN)n repeats within the AR gene in men from 51 high-risk prostate cancer sibships, which included at least one affected and one unaffected man (n = 210). We compared repeat lengths of men with prostate cancer (n = 140) to their brothers (n = 70) without disease, stratified by median age at diagnosis of affected men within each sibship. Conditional logistic regression was used to compute odds ratios (OR) and 95% confidence intervals to evaluate associations between prostate cancer and repeat length. RESULTS: The OR for prostate cancer associated with short (CAG)n repeats (< 22) compared to longer repeats (> or =22) was 1.13 (95% CI 0.5-2.4) overall, but was higher in sibships with a median age of <66 years at diagnosis (OR = 1.72, 95% CI 0.5-6.0). The (GGN)n array also was not associated with prostate cancer in general. However, in older men (> or = 66 years), there was a modest elevation in risk (OR = 1.56, 95% CI 0.6-4.1) among those with short repeats (GGN of < or =16). Men with both a short (CAG)n (< 22) and a short (GGN)n (< or =16) array were not at higher risk (OR = 1.06) compared to men with two long repeats [(CAG)n > or =22 and (GGN)n >16)]. CONCLUSIONS: These results suggest that the (CAG)n and (GGN)n repeats in the AR gene do not play a major role in familial prostate cancer.  相似文献   

12.
Programmed cell death in varicocele-bearing testes   总被引:1,自引:0,他引:1  
Accelerated apoptosis is a significant factor in the pathophysiology of male infertility disorders associated with abnormal spermatogenesis. This study aimed to investigate apoptosis in varicocele-bearing testes. Sixty four men with varicocele (18 fertile and 46 infertile) were studied compared with eight men with obstructive azoospermic as controls. Apoptosis was assessed in testicular biopsy specimens using terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) method as well as electron microscopy. The results demonstrated that the occurrence of apoptotic changes comprised all types of germ cells but not affecting Sertoli cells. Mean tubular apoptotic indices of fertile or infertile men with varicocele were significantly higher than controls (mean ± SD 4.55 ± 1.03%, 6.29 ± 1.82% versus 2.71 ± 0.45%, P  < 0.05). Mean Leydig cells apoptotic indices of infertile men with varicocele were significantly higher than those of fertile men without varicocele as well as controls (1.18 ± 0.38%, 0.68 ± 0.15%, 0.31 ± 0.21%, P  < 0.05). Apoptotic indices were nonsignificantly correlated with Johnsen score, testicular volume or varicocele grade. It is concluded that testicular apoptosis is increased in varicocele-associated men either fertile or infertile who may be implicated in associated spermatogenic dysfunction.  相似文献   

13.
A retrospective case–control study was carried out in the Han-Chinese population to determine the polymorphisms of xeroderma pigmentosum complementation group C ( XPC ) gene on the risk of idiopathic azoospermia or oligozoospermia. The Ala499Val (C>T) and Lys939Gln (A>C) polymorphism of XPC gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism in three groups of infertile men (172 patients of azoospermia, 25 patients of severe oligozoospermia, 55 patients of oligozoospermia) and 228 fertile men. Increased risk of idiopathic azoospermia, but not oligozoospermia was associated with the XPC variant genotypes of Ala499Val (C>T) [adjusted odds ratio (OR) = 1.67, 95% confidence interval (CI) = 1.04–2.68 for CT heterozygote and adjusted OR = 2.03, 95% CI = 1.10–3.75 for TT homozygote] compared with CC homozygous wide-type. The Lys939Gln (A>C) polymorphism was not related to spermatogenic failure. The combined risk alleles analysis and haplotype analysis showed that ORs increased as the number of the risk alleles increased and the 499T-939C haplotype had a significantly increased risk of idiopathic azoospermia (OR = 7.97; 95% CI = 3.51–18.07) compared with other haplotypes. The results suggest that XPC Ala499Val (C>T) polymorphism is correlated with high risk of idiopathic azoospermia in the Han-Chinese population.  相似文献   

14.
CAG repeat expansion in exon 1 of the androgen receptor (AR) gene has been reported to be associated with male infertility in some but not all populations. Until now, studies have not been carried out to examine this among Indian populations. For the first time, we have analyzed the CAG repeat motif in the AR gene in 280 men with azoospermia and in 201 men with normal fertility. The mean number of CAG repeats in the AR gene of men with azoospermia was 21.7 +/- 0.18, with a high incidence of repeat number 22. Among fertile-control men, the mean number of CAG repeats was 22.4 +/- 0.19, with a predominance of repeat number 23. The highest number of CAG repeats (32) was found with low frequency in both fertile and azoospermic groups. Comparison of fertile men and those with azoospermia on the basis of CAG repeats revealed that the number of CAG repeats in both groups were similar, as revealed with a paired t test (t = 0.04; P =.967). Expansion of the CAG repeat in the AR gene is therefore not associated with male infertility in Indian populations. This suggests that what is true for one population may not be true for other populations.  相似文献   

15.
16.
In our study, we analyzed chromosomal abnormalities, Y chromosome deletions, androgen receptor CAG repeat length and their association with defective spermatogenesis in infertile Mexican men. Eighty-two infertile patients and 40 controls were screened for karyotypic abnormalities, Y chromosome microdeletions, and CAG repeats. Nine infertile males (11%) carried chromosomal abnormalities and 10 (12.2%) presented Y chromosome microdeletions. The mean CAG repeat length was 21.6 and 20.88 base pairs in idiopathic infertile males and controls, respectively. Our results suggest that chromosomal aberrations and Y-chromosomal microdeletions are related to male infertility in Mexican men. In addition, expansion of the CAG repeat segments of the androgen receptor is not correlated with male idiopathic infertility.  相似文献   

17.
This study was performed to examine the contribution of genetic polymorphism of oestrogen and androgen receptor (AR) genes in male infertility. We have studied in total 173 Greek men, 109 infertile patients and 64 controls (group A). Patients were divided in to three subgroups: group B (n=29) with idiopathic moderate oligospermia, group C (n=42) with azoospermia or idiopathic severe oligospermia and group D (n=38) with azoospermia or oligospermia of various known aetiologies. All patients and controls were genotyped for two polymorphisms of the oestrogen receptor alpha (ERalpha) gene and also for the (CAG)n repeat length polymorphism of the X-linked androgen receptor (AR)gene. The control group had statistically significant difference from group C regarding the XbaI polymorphism of ERalpha gene. Despite the fact that we did not observe any statistically significant differences in the mean and range of the CAG repeat number, the frequency of the higher repeats of the nucleotide repeat sequence (CAG)n of the AR gene was 2-4 times higher in groups B and C compared with the control group A. Our results indicate that both ERalpha and AR gene play significant role in male fertility. It is possible that a synergy may exist between unfavourable genotypes of these two genes in male infertility.  相似文献   

18.
During recent years several studies have suggested that a slight increase in the number of CAG repeat sequences in exon 1 of the androgen receptor gene causes idiopathic oligozoospermia. We tested whether CAG repeats are more numerous in men with idiopathic infertility compared to those with known causes of oligozoospermia. CAG repeats were analysed in a consecutive sample of 217 infertile men covering a wide range of diagnoses and sperm counts. Data were compared with those of a control group of 131 normozoospermic men including 62 fathers. CAG repeats (x +/- SD) did not differ between idiopathically (21.4 +/- 2.9) and non-idiopathically infertile men (21.6 +/- 2.8) or normozoospermic men of unproven fertility (20.6 +/- 3.0). Only fathers had significantly fewer repeats (19.4 +/- 3.1; p < 0.001). Different from controls, no correlation between CAG repeats and any semen parameter existed in patients. Comparison of our and published studies showed that odds ratios for infertility in men with CAG repeat length in the upper quartile of the normal range increased when the controls were selected by proven fertility. We conclude that more numerous CAG repeats do not directly cause oligozoospermia and propose that men with longer CAG repeats might be more prone to develop infertility in response to any pathogen/epigenetic factors.  相似文献   

19.
Male fertility largely depends on sperm quality, which may be affected by environmental and genetic factors. Recent data emphasised the implication of the polymorphism of mitochondrial DNA polymerase gamma (POLG) CAG repeats in male infertility. In this report, we explored a possible role of the (POLG) gene polymorphism in male infertility in Tunisian men. The polymorphic CAG repeat in the nuclear POLG gene was studied in 339 male subjects (216 patients with infertility (69 azoospermic, 115 oligoasthenoteratospermic and 32 normospermic) and 123 fertile) after DNA amplification by PCR, followed by genotyping using an automatic sequencer. The heterozygous and the homozygous mutant genotypes (10/ ≠ 10 and ≠ 10/ ≠ 10) were significantly more frequent among infertile patients than among fertile controls (11.2% versus 1.6%, P = 1.3 × 10(-3) and 4.6% versus 0.8%, P = 4.2 × 10(-7) respectively). We also found a significant difference between the frequencies of 10/ ≠ 10 genotype in azoospermic (4.4%) and in oligoasthenoteratospermic (15.6%) infertile patients (P = 2.6 × 10(-2) ). However, the homozygous mutant genotype (≠ 10/ ≠ 10) was seen at similar frequencies in azoospermic, normospermic and oligoasthenospermic men (4.4%, 3.1% and 5.2% respectively). Under our conditions, the findings showed an association between POLG CAG repeat polymorphism and male infertility in Tunisian population.  相似文献   

20.
The activity of androgen receptor (AR) is modulated by a polymorphic CAG trinucleotide repeat in the AR gene. In the present study, we investigated hormonal changes among ageing men, and whether the number of AR CAG triplets is related to the appearance of these changes, as well as symptoms and diseases associated with ageing. A total of 213 41-70-year-old men donated blood for hormone analyses (LH, testosterone, oestradiol and SHBG) and answered questions concerning diseases and symptoms associated with ageing and/or androgen deficiency. Of these men, 172 donated blood for the measurement of the CAG repeat length of AR. The CAG repeat region of the AR gene was amplified by polymerase chain reaction (PCR) and the products were sized on polyacrylamide gels. The repeat number was analysed as a dichotomized variable divided according to cut-off limits of the lowest (< or =20 repeats) and the highest quartile (> or =23 repeats), and as a continuous variable. The proportion of men with serum LH in the uppermost quartile (>6.0 IU/L) with normal serum testosterone (>9.8 nmol/L, above the lowest 10%) increased significantly with age (p = 0.01). There were fewer men with this hormonal condition among those with CAG repeat number in the uppermost quartile (> or =23 repeats) (p = 0.03). These men also reported less decreased potency (p < 0.05). The repeat number was positively correlated with depression, as expressed by the wish to be dead (r = 0.45; p < 0.0001), depressed mood (r = 0.23; p = 0.003), anxiety (r = 0.15; p < 0.05), deterioration of general well-being (r = 0.22; p = 0.004), as well as decreased beard growth (r = 0.49; p < 0.0001). A hormonal condition where serum testosterone is normal but LH increased is a frequent finding in male ageing. Only certain types of age-related changes in ageing men were associated with the length of the AR gene CAG repeat, suggesting that this parameter may play a role in setting different thresholds for the array of androgen actions in the male.  相似文献   

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