1
|
Androgen Receptor Gene CAG Repeat Length Varies and Affects Semen Quality in an Ethnic-Specific Fashion in Young Men from Russia. Int J Mol Sci 2022; 23:ijms231810594. [PMID: 36142533 PMCID: PMC9505661 DOI: 10.3390/ijms231810594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/04/2022] [Accepted: 09/09/2022] [Indexed: 11/16/2022] Open
Abstract
Male infertility is a multi-factorial and multi-genetic disorder, and the prevalence of male infertility in the world is estimated at 5–35%. The search for the causes of male infertility allowed for identifying a number of genetic factors including a single X-linked gene of the androgen receptor (AR), and some of its alleles are assumed to negatively affect male fertility. Our aim was (1) to study the variability of the length of CAG repeats of the AR gene and possible associations in the AR CAG genetic variants with semen quality and reproductive hormone levels in a population-based cohort of men and (2) to estimate distributions of AR CAG repeat alleles and associations with semen parameters in different ethnic subgroups. The cohort of 1324 young male volunteers of different ethnicities (median age 23.0 years) was recruited from the general population of five cities of the Russian Federation, regardless of their fertility status. Semen quality (sperm concentration, motility and morphology), reproductive hormone levels (testosterone, estradiol, LH, FSH and inhibin B) and trinucleotide (CAG) n repeat polymorphism in exon 1 of the AR gene were evaluated. The semen samples were analyzed according to the WHO laboratory manual (WHO, 2010), serum hormones were measured by enzyme immunoassay, and the AR CAG repeat length was analyzed by direct sequencing of leukocyte DNA. The median AR CAG repeat length in men of our multi-ethnic population was 23 (range 6–39). In the entire study population, a significant difference (p ≤ 0.05) was found in the frequency distribution and the mean values for the CAG repeat length between the groups with normal (23.2 ± 3.3) and impaired semen quality (23.9 ± 3.2). Additionally, we demonstrated that the total sperm count, sperm concentration, progressive motility and normal morphology were lower in the category of long CAG repeats (CAG ≥ 25) compared with those in the category of short CAG repeats (CAG ≤ 19); however, hormonal parameters did not differ between the long and short CAG categories, with the exception of estradiol. Significant differences were observed in the AR CAG repeat length between the most common ethnic cohorts of Slavs (Caucasians), Buryats (Asians), and Yakuts (Asians). The Buryats and Yakuts had a higher number of CAG repeats than the Slavs (medians: Slavs—23; Buryats—24; Yakuts—25). The range of alleles differed among ethnicities, with the Slavs having the largest range (7–36 repeats, 24 alleles total), the Yakuts having the smallest range (18–32 repeats, 14 alleles total) and the Buryats having the middle range (11–39 repeats, 20 alleles total). The longer CAG repeats were associated with an impaired semen quality within the Slavic (CAG ≥ 25) and Buryat (CAG ≥ 28) groups, but this effect was not found in Yakuts. Hormonal parameters did not differ between the three CAG repeat categories in men of all ethnic groups. This is the largest Russian study of the distribution of AR CAG repeats and the search for association between length of AR CAG repeat tract and impaired spermatogenesis in men from the general population. Our results confirmed the association of longer CAG repeats with a risk of impaired semen quality, but this association can be modified by ethnic origin. Identification of the number of AR CAG repeats can be an effective tool to assess the risk of male subfertility and the control of androgen hormone therapy of reproductive diseases.
Collapse
|
2
|
Osadchuk LV, Osadchuk AV. Role of CAG and GGC Polymorphism of the Androgen Receptor Gene in Male Fertility. RUSS J GENET+ 2022. [DOI: 10.1134/s1022795422020119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
3
|
Metin Mahmutoglu A, Hurre Dirie S, Hekim N, Gunes S, Asci R, Henkel R. Polymorphisms of androgens-related genes and idiopathic male infertility in Turkish men. Andrologia 2021; 54:e14270. [PMID: 34632603 DOI: 10.1111/and.14270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 09/24/2021] [Indexed: 01/01/2023] Open
Abstract
Androgens, testosterone and dihydrotestosterone (DHT) are endocrine regulators of spermatogenesis and act via androgen receptor (AR). The aim of this study was to investigate the association(s) of AR (CAG repeat length), SRD5A2 (rs523349, V89L) and TNF-α (rs1800629, -308G/A) polymorphisms with idiopathic male infertility in Turkish men. This case-control study consisted of 312 men with idiopathic infertility and 113 fertile men. Polyacrylamide gel electrophoresis (PAGE) or PCR-restriction fragment length polymorphism methods were used for genotyping. The mean AR CAG repeat length was significantly longer in infertile men than in fertile men (p = 0.015). However, there was no significant association between the SRD5A2 genotypes (VV, VL and LL) and the risk of infertility (p = 0.516). The genotype frequency and allele distribution of TNF-α -308G/A polymorphism (GG, GA, AA genotypes and G, A alleles) were not associated with male infertility (p = 0.779 and p = 0.743 respectively). AR CAG repeat expansion might be one of the risk factors for idiopathic male infertility in Turkish men. Further studies investigating the association of male infertility with AR CAG, V89L and -308G/A polymorphisms are warranted to understand the possible associations among them.
Collapse
Affiliation(s)
- Asli Metin Mahmutoglu
- Faculty of Medicine, Department of Medical Biology, Ondokuz Mayis University, Samsun, Turkey
| | - Saadiq Hurre Dirie
- Faculty of Medicine, Department of Medical Biology, Ondokuz Mayis University, Samsun, Turkey
| | - Neslihan Hekim
- Faculty of Medicine, Department of Medical Biology, Ondokuz Mayis University, Samsun, Turkey
| | - Sezgin Gunes
- Faculty of Medicine, Department of Medical Biology, Ondokuz Mayis University, Samsun, Turkey.,Health Sciences Institute, Department of Multidisciplinary Molecular Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Ramazan Asci
- Health Sciences Institute, Department of Multidisciplinary Molecular Medicine, Ondokuz Mayis University, Samsun, Turkey.,Faculty of Medicine, Department of Urology, Ondokuz Mayis University, Samsun, Turkey
| | - Ralf Henkel
- Department of Medical Bioscience, University of the Western Cape, Bellville, South Africa.,American Center for Reproductive Medicine, Cleveland Clinic, Cleveland, Ohio, USA.,Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
| |
Collapse
|
4
|
Al Zoubi MS, Bataineh H, Rashed M, Al-Trad B, Aljabali AAA, Al-Zoubi RM, Al Hamad M, Issam AbuAlArjah M, Batiha O, Al-Batayneh KM. CAG Repeats in the androgen receptor gene is associated with oligozoospermia and teratozoospermia in infertile men in Jordan. Andrologia 2020; 52:e13728. [PMID: 32583490 DOI: 10.1111/and.13728] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/09/2020] [Accepted: 05/28/2020] [Indexed: 01/06/2023] Open
Abstract
CAG trinucleotide repeats are coded for the polyglutamine tract in the N-terminal of the androgen receptor (AR) gene which varies in normal individuals from 6 to 36 residues. In this study, we inspected the impact of the CAG repeats on the spermatogenic defects by measuring the size of AR-CAG repeats length in a cohort of 260infertile and 169 fertile Jordanian men. The infertile group included three subgroups of a zoospermic, oligozoospermic and teratozoospermia men. The CAG allele size was determined by direct sequencing. The results showed a significant association between the length of the AR-CAG repeats and men's infertility (p = .001). In particular, the current cohort demonstrated a significant association between the AR-CAG length polymorphism and oligozoospermia (p < .001) and teratozoospermia (p < .001) but not azoospermia. According to distributions of allele frequency, the risk of oligozoospermia was 5.5-fold greater than normal when alleles frequency > 20 repeats, while the risk of teratozoospermia was > 10.6 folds greater than normal when allele frequency > 22 repeats. In conclusion, our results underscored that the long repeats of the AR-CAG polymorphism within the normal range might be associated with abnormal spermatogenesis such as teratozoospermia and oligozoospermia and contributing to infertility in Jordanian men.
Collapse
Affiliation(s)
- Mazhar Salim Al Zoubi
- Department of Basic Medical Sciences, Faculty of Medicine, Yarmouk University, Irbid, Jordan
| | - Hamzah Bataineh
- Department of Biological Sciences, Faculty of Science, Yarmouk University, Irbid, Jordan
| | - Mitri Rashed
- King Hussein Medical Centre, Royal Medical Services, Amman, Jordan
| | - Bahaa Al-Trad
- Department of Biological Sciences, Faculty of Science, Yarmouk University, Irbid, Jordan
| | - Alaa A A Aljabali
- Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Yarmouk University, Irbid, Jordan
| | - Raed M Al-Zoubi
- Department of Chemistry, Jordan University of Science & Technology, Irbid, Jordan
| | - Mohammad Al Hamad
- Department of Pathology, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Manal Issam AbuAlArjah
- Department of Basic Medical Sciences, Faculty of Medicine, Yarmouk University, Irbid, Jordan
| | - Osamah Batiha
- Department of applied biological sciences, Jordan University of Science and Technology, Irbid, Jordan
| | - Khalid M Al-Batayneh
- Department of Biological Sciences, Faculty of Science, Yarmouk University, Irbid, Jordan
| |
Collapse
|
5
|
Mobasseri N, Babaei F, Karimian M, Nikzad H. Androgen receptor ( AR)-CAG trinucleotide repeat length and idiopathic male infertility: a case-control trial and a meta-analysis. EXCLI JOURNAL 2018; 17:1167-1179. [PMID: 30713477 PMCID: PMC6341423 DOI: 10.17179/excli2018-1744] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Accepted: 11/15/2018] [Indexed: 01/22/2023]
Abstract
CAG trinucleotide repeats in androgen receptor (AR) gene encode a polyglutamine tract in AR N-terminal transactivation domain. Studies have been conducted to evaluate the effect of CAG repeat length on male infertility, which have yielded contradictory results. This study aimed to explore the number of AR-CAG repeats in 150 fertile controls and 150 idiopathic infertile men, divided into four azoospermia, oligozoospermia, asthenozoospermia, and teratozoospermia subgroups. In addition, a meta-analysis was conducted based on previous studies to assess the association of the mentioned variation with male infertility in recent years. Polymerase chain reaction (PCR) targeting followed by an electrophoresis on polyacrylamide gel was used for AR-CAG genotype detecting. Moreover, a systematic search was performed in PubMed, Web of Science, Science Direct, and Google Scholar databases to collect eligible studies for meta-analysis purpose. According to the results, a significant association was observed between increased length of AR-CAG polymorphism and male infertility (p< 0.0001). Furthermore, there were similar significant associations in the azoospermia (p= 0.048), asthenozoospermia (p= 0.013) and teratozoospermia (p= 0.002) subgroups. In addition, meta-analysis on forty studies showed a significant association between AR-CAG polymorphism in the overall analysis (SMD= 0.199, 95 % CI= 0.112-0.287, p<0.001) and the Caucasian subgroup (SMD= 0.151, 95 % CI= 0.040-0.263, p= 0.008). Our results elucidated that long stretches of CAG repeat might lead to AR dysfunction, contributing to male infertility especially in the Caucasian population.
Collapse
Affiliation(s)
- Narges Mobasseri
- Gametogenesis Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | - Faezeh Babaei
- Gametogenesis Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | - Mohammad Karimian
- Gametogenesis Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | - Hossein Nikzad
- Gametogenesis Research Center, Kashan University of Medical Sciences, Kashan, Iran
| |
Collapse
|
6
|
Khan HL, Bhatti S, Abbas S, Khan YL, Gonzalez RMM, Aslamkhan M, Gonzalez GR, Aydin HH. Serotonin transporter (5-HTTLPR) genotypes and trinucleotide repeats of androgen receptor exert a combinatorial effect on hormonal milieu in patients with lifelong premature ejaculation. Andrology 2018; 6:916-926. [DOI: 10.1111/andr.12518] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 04/26/2018] [Accepted: 06/01/2018] [Indexed: 12/18/2022]
Affiliation(s)
- H. L. Khan
- Lahore Institute of Fertility and Endocrinology; Hameed Latif Hospital; Lahore Pakistan
| | - S. Bhatti
- Lahore Institute of Fertility and Endocrinology; Hameed Latif Hospital; Lahore Pakistan
- Department of Human Genetics and Molecular biology; University of Health Sciences; Lahore Pakistan
- Department of Medical Education; Rashid Latif Medical College; Lahore Pakistan
| | - S. Abbas
- Lahore Institute of Fertility and Endocrinology; Hameed Latif Hospital; Lahore Pakistan
| | - Y. L. Khan
- Lahore Institute of Fertility and Endocrinology; Hameed Latif Hospital; Lahore Pakistan
| | - R. M. M. Gonzalez
- Centro de investigacion Biomedica de Occidente; IMSS; Uiversidad de Guadalajara; Guadalajara Jalisco Maxico
| | - M. Aslamkhan
- Department of Human Genetics and Molecular biology; University of Health Sciences; Lahore Pakistan
| | - G. R. Gonzalez
- Universidad De Guadalajara CIBO; IMSS; Guadalajara Jalisco Maxico
| | - H. H. Aydin
- Department of Medical Biochemistry; Ege University School of Medicine; Bornova Izmir Turkey
| |
Collapse
|
7
|
Xiao F, Lan A, Lin Z, Song J, Zhang Y, Li J, Gu K, Lv B, Zhao D, Zeng S, Zhang R, Zhao W, Pan Z, Deng X, Yang X. Impact of CAG repeat length in the androgen receptor gene on male infertility - a meta-analysis. Reprod Biomed Online 2016; 33:39-49. [PMID: 27157932 DOI: 10.1016/j.rbmo.2016.03.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 03/31/2016] [Accepted: 03/31/2016] [Indexed: 12/18/2022]
Abstract
CAG repeats are polymorphic nucleotide repeats present in the androgen receptor gene. Many studies have estimated the association between CAG repeat length and male infertility, but the conclusions are controversial. Previous meta-analyses have come to different conclusions; however, new studies have been published. An updated meta-analysis was conducted. PubMed, CBM, CNKI and Web of Science databases were systematically searched for studies published from 1 January 2000 to 1 October 2015. Case-control studies on the association between CAG repeat length and male infertility using appropriate methodology were included. Forty studies were selected, including 3858 cases and 3161 controls. Results showed statistically significantly longer CAG repeat length among cases compared with controls (SMD = 0.14; 95% CI, 0.02-0.26). Shorter repeat length was associated with a lower risk of male infertility compared with a longer repeat length in the overall analysis (OR = 0.79, 95% CI: 0.66-0.95). Moreover, CAG repeat length was associated with male infertility in Caucasian populations, but not Asian or Egyptian populations. Subgroup analysis revealed no significant difference in German populations, but CAG repeat length was associated with male infertility in China and the USA. There were no significant differences between cases and controls in azoospermia and severe oligozoospermia.
Collapse
Affiliation(s)
- Feifan Xiao
- The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China; Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China
| | - Aihua Lan
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China
| | - Zhidi Lin
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China; Department of Urology, Affiliated Hospital of Youjiang Medical College for Nationalities, Baise, Guangxi, China
| | - Jianfei Song
- The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Yuening Zhang
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China
| | - Jiatong Li
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China
| | - Kailong Gu
- Department of Urology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Baihao Lv
- Department of Urology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Dong Zhao
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China
| | - Siping Zeng
- Urology Medical Research Center, Department of Guangxi Medical University Affiliated Hospital, Nanning, Guangxi, China
| | - Ruoheng Zhang
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China
| | - Wei Zhao
- First Clinical Academy, Guangxi Medical University, Nanning, Guangxi, China
| | - Zhengyan Pan
- First Clinical Academy, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaozhen Deng
- First Clinical Academy, Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaoli Yang
- Medical Scientific Research Center, Guangxi Medical University, Nanning, Guangxi, China.
| |
Collapse
|
8
|
Pan B, Li R, Chen Y, Tang Q, Wu W, Chen L, Lu C, Pan F, Ding H, Xia Y, Hu L, Chen D, Sha J, Wang X. Genetic Association Between Androgen Receptor Gene CAG Repeat Length Polymorphism and Male Infertility: A Meta-Analysis. Medicine (Baltimore) 2016; 95:e2878. [PMID: 26962784 PMCID: PMC4998865 DOI: 10.1097/md.0000000000002878] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The association between polymorphism of androgen receptor gene CAG (AR-CAG) and male infertility in several studies was controversial. Based on studies on association between AR-CAG repeat length and male infertility in recent years, an updated meta-analysis is needed. We aimed to evaluate the association between AR-CAG repeat length and male infertility in advantage of the data in all published reports.We searched for reports published before August 2015 using PubMed, CNKI, VIP, and WanFang. Data on sample size, mean, and standard deviation (SD) of AR-CAG repeat length were extracted independently by 3 investigators.Forty-four reports were selected based on criteria. The overall infertile patients and azoospermic patients were found to have longer AR-CAG repeat length (standard mean difference (SMD) = 0.19, 95% confidence interval (CI): 0.10-0.28, P < 0.01; SMD = 0.36, 95% CI: 0.10-0.61, P < 0.01). AR-CAG repeat length was longer in infertile men in Asian, Caucasian, and mixed races (SMD = 0.25, 95% CI: 0.08-0.43, P <0.01; SMD = 0.13, 95% CI: 0.02-0.25, P <0.05; SMD = 0.39, 95% CI: 0.15-0.63, P <0.01). The overall study shows that increased AR-CAG repeat length was associated with male infertility. The subgroup study on races shows that increased AR-CAG repeat length was associated with male infertility in Asian, Caucasian, and mixed races. Increased AR-CAG repeat length was also associated with azoospermia.This meta-analysis supports that increased androgen receptor CAG length is capable of causing male infertility susceptibility.
Collapse
Affiliation(s)
- Bihui Pan
- From the State Key Laboratory of Reproductive Medicine (BP, RL, YC, WW, CL, YX, XW), Institute of Toxicology, School of Public Health; Key Laboratory of Modern Toxicology of Ministry of Education (BP, RL, YC, WW, CL, YX, XW), Nanjing Medical University; State Key Laboratory of Reproductive Medicine (QT, HD), Department of Obstetrics, Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing; State Key Laboratory of Reproductive Medicine (WW, LH, DC), Wuxi Maternal and Child Health Care Hospital Affiliated to Nanjing Medical University, Wuxi; Department of Gynecology and Obstetrics (LC), The Second Affiliated Hospital of Nantong University, Nantong; State Key Laboratory of Reproductive Medicine (FP), Department of Andrology, Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University; and State Key Laboratory of Reproductive Medicine (JS), Nanjing Medical University, Nanjing, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Mostafa T, El-Shahid LH, El Azeem AA, Shaker O, Gomaa H, Abd El Hamid HM. Androgen receptor-CAG repeats in infertile Egyptian men. Andrologia 2011; 44:147-51. [PMID: 21714804 DOI: 10.1111/j.1439-0272.2010.01125.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
This study aimed to assess the androgen receptor (AR) codon amino acids glutamine (CAG) repeats in 185 Egyptian men divided into fertile controls (n = 30), oligoasthenoteratozoospermic (OAT) men (n = 35), nonobstructive azoospermic (NOA) men (n = 120; 18 successful testicular sperm extraction (TESE) and 102 unsuccessful TESE cases). They were subjected to history taking, genital examination, semen analysis, testicular biopsies for NOA cases, serum hormones and CAG repeats by PCR. The mean AR-CAG repeats showed significant difference between NOA group compared with fertile controls or OAT groups. Nonsignificant difference was elicited between OAT group and fertile controls. In NOA cases, CAG repeats demonstrated nonsignificant difference between unsuccessful and successful TESE. AR-CAG repeats elicited significant negative correlation with sperm count, significant positive correlation with sperm normal forms percentage and nonsignificant correlations with sperm motility per cent, tested serum hormones or testicular volume. It is concluded that AR-CAG repeats in Egyptian infertile men are in the range of other international or regional studies. AR-CAG repeats have demonstrated nonsignificant difference regarding TESE outcome in NOA cases.
Collapse
Affiliation(s)
- T Mostafa
- Department of Andrology & Sexology, Faculty of Medicine, Cairo University, Egypt.
| | | | | | | | | | | |
Collapse
|
10
|
Role of genetics in azoospermia. Urology 2010; 77:598-601. [PMID: 21195467 DOI: 10.1016/j.urology.2010.10.001] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 09/17/2010] [Accepted: 10/03/2010] [Indexed: 01/17/2023]
Abstract
OBJECTIVE To review established genetic causes of azoospermia, the most severe form of male infertility, and help clinicians, scientists, and infertile couples considering assisted reproductive technologies (ART) to understand the complexity of the disorder and to maximize the chances of having a healthy infant through proper counseling and treatment. METHOD An initial literature search was performed on PubMed using the key words "azoospermia" "oligospermia," and "genetics." The results were limited to the studies on humans and written in English, which were written within last 10 years. Although preliminary query results showed more than 900 articles, further queries using key words, such as "Y chromosome," "monogenics," "aneuploidy," "mitochondrial DNA," and "epigenetics," along with "azoospermia," narrowed the results to 30 papers, which were included in the present study. RESULTS Genetic defects causing azoospermia were categorized into two large categories: chromosomal and nonchromosomal. Chromosomal defects were further categorized into (1) structural abnormalities, such as Y chromosome micro/macrodeletions, chromosomal inversions, and translocations; and (2) numerical abnormalities, also known as aneuploidy. Nonchromosomal defects included sperm mitochondrial genome defects and epigenetic alterations of genome. CONCLUSIONS As a result of advancements in ART, understanding the potential implications of genetic disorders for infertile couples is critical. Analysis of a potential genetic role in azoospermia holds promise to expand our knowledge to evaluate male infertility and to guide treatments.
Collapse
|
11
|
Nenonen HA, Giwercman A, Hallengren E, Giwercman YL. Non-linear association between androgen receptor CAG repeat length and risk of male subfertility--a meta-analysis. ACTA ACUST UNITED AC 2010; 34:327-32. [PMID: 20579136 DOI: 10.1111/j.1365-2605.2010.01084.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The CAG repeat in the androgen receptor (AR) has been widely studied in association with male infertility, but the results are conflicting. In a recent meta-analysis, infertile men had <1 repeat longer CAG stretch than fertile men when analysed in a linear regression model assuming that AR function diminishes with increasing CAG length. However, in vitro, a non-linear activity pattern was recently demonstrated so that ARs containing short and long stretches, respectively, displayed lower activity than the AR of median length. These results prompted us to explore the possible association between CAG number and male infertility risk in a stratified manner on the basis of data from the mentioned meta-analysis and subjects from our clinical unit. The study population included 3915 men, 1831 fertile and 2084 infertile. Data were divided into three categories: CAG<22, CAG 22-23 (reference) and CAG>23 and analysed in a binary logistic regression model. Men with CAG<22 and CAG>23 had 20% increased odds ratio of infertility compared with carriers of the median lengths [for CAG<22: p=0.03, 95% confidence interval (CI): 1.02-1.39; for CAG>23: p=0.02, 95% CI: 1.03-1.44]. These results show that an alternative model to a linear one for the genotype-phenotype association in relation to AR CAG repeats is likely, as lengths close to the median confine lowest risk of infertility.
Collapse
Affiliation(s)
- H A Nenonen
- Department of Clinical Sciences, Molecular Genetic Reproductive Medicine, Lund University Reproductive Medicine Centre, Molecular Reproductive Medicine Research Unit, Malmö University Hospital, Lund University, Malmö, Sweden.
| | | | | | | |
Collapse
|
12
|
Westerveld H, Visser L, Tanck M, van der Veen F, Repping S. CAG repeat length variation in the Androgen Receptor gene is not associated with spermatogenic failure. Fertil Steril 2008; 89:253-9. [PMID: 17889867 DOI: 10.1016/j.fertnstert.2007.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 02/02/2007] [Accepted: 02/02/2007] [Indexed: 11/19/2022]
Abstract
Previous association studies that described the effect of an enlarged CAG repeat length in the Androgen Receptor (AR) gene on spermatogenesis could not prove or refute a true association because of methodological weaknesses. Here, we clearly show that there is no association between CAG repeat length variation and semen quality.
Collapse
Affiliation(s)
- Henrike Westerveld
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, the Netherlands.
| | | | | | | | | |
Collapse
|
13
|
Davis-Dao CA, Tuazon ED, Sokol RZ, Cortessis VK. Male infertility and variation in CAG repeat length in the androgen receptor gene: a meta-analysis. J Clin Endocrinol Metab 2007; 92:4319-26. [PMID: 17684052 DOI: 10.1210/jc.2007-1110] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
CONTEXT Many studies have investigated the association between male infertility and trinucleotide repeat polymorphisms in the androgen receptor (AR) gene, but no comprehensive meta-analysis of all published studies has been conducted. OBJECTIVE Our goals were to summarize published data on associations between AR CAG and GGC repeat lengths and male infertility and investigate sources of variation between study results. DATA SOURCES We searched for reports published before October 2006 using Medline, PubMed, and Web of Science. STUDY SELECTION All selected studies included the following: a case group with infertility as measured by semen parameters, a control group of known or presumed fertile men, and measurement of CAG and/or GGC repeat lengths among cases and controls. Thirty-nine reports were selected based on these criteria, and 33 were ultimately included in the meta-analysis. DATA EXTRACTION One investigator extracted data on sample size, mean and sd of trinucleotide repeat length, and study characteristics. DATA SYNTHESIS Estimates of the standardized mean difference (95% confidence interval) were 0.19 (0.09-0.29) for the 33 studies and 0.31 (0.14-0.47) for a subset of 13 studies that used more stringent case and control selection criteria. Thus, in both groups, cases had statistically significantly longer CAG repeat length than controls. Publication date appeared to be a significant source of variation between studies. CONCLUSIONS This meta-analysis provides support for an association between increased androgen receptor CAG length and idiopathic male infertility, suggesting that even subtle disruptions in the androgen axis may compromise male fertility.
Collapse
Affiliation(s)
- Carol A Davis-Dao
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, 1441 Eastlake Avenue, MC-9175, Los Angeles, California 90033, USA
| | | | | | | |
Collapse
|
14
|
Peterlin B, Zorn B, Teran N, Kunej T. Analysis of the CAG repeat number in exon 1 of the androgen receptor gene in Slovene men with idiopathic azoospermia and oligoasthenoteratozoospermia. Asian J Androl 2007; 9:280-2. [PMID: 17334597 DOI: 10.1111/j.1745-7262.2007.00242.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
15
|
Abstract
Androgen receptor (AR) gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat (CAG and GGN) length polymorphisms have been an additional subject of interest and controversy among geneticists. The polymorphic variations in triplet repeats have been associated with a number of disorders, but at the same time contradictory findings have also been reported. Further, studies on the same disorder in different populations have generated different results. Therefore, combined analysis or review of the published studies has been of much value to extract information on the significance of variations in the gene in various clinical conditions. AR genetics has been reviewed extensively but until now review articles have focused on individual clinical categories such as androgen insensitivity, male infertility, prostate cancer, and so on. We have made the first effort to review most the aspects of AR genetics. The impact of androgens in various disorders and polymorphic variations in the AR gene is the main focus of this review. Additionally, the correlations observed in various studies have been discussed in the light of in vitro evidences available for the effect of AR gene variations on the action of androgens.
Collapse
MESH Headings
- Androgen-Insensitivity Syndrome/genetics
- Androgen-Insensitivity Syndrome/physiopathology
- Bone Diseases, Metabolic/genetics
- Bone Diseases, Metabolic/physiopathology
- Breast Neoplasms/genetics
- Breast Neoplasms/physiopathology
- Cognition Disorders/genetics
- Cognition Disorders/physiopathology
- Digestive System Diseases/genetics
- Digestive System Diseases/physiopathology
- Female
- Genital Neoplasms, Female/genetics
- Genital Neoplasms, Female/physiopathology
- Genital Neoplasms, Male/genetics
- Genital Neoplasms, Male/physiopathology
- Humans
- Infertility, Male/genetics
- Male
- Muscular Atrophy, Spinal/genetics
- Muscular Atrophy, Spinal/physiopathology
- Phenotype
- Point Mutation
- Polycystic Ovary Syndrome/genetics
- Polycystic Ovary Syndrome/physiopathology
- Polymorphism, Genetic
- Pre-Eclampsia/genetics
- Pre-Eclampsia/physiopathology
- Pregnancy
- Receptors, Androgen/genetics
- Receptors, Androgen/physiology
- Schizophrenia/genetics
- Schizophrenia/physiopathology
- Testosterone/deficiency
- Trinucleotide Repeats
Collapse
Affiliation(s)
- Singh Rajender
- Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
| | | | | |
Collapse
|