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BACKGROUND: Infertile men with multiple morphological abnormalities of the sperm flagella (MMAF) phenotype exhibit mosaic sperm flagella abnormalities such as short, bent, coiled, and irregular flagella or absent flagella. Sperm flagellum has an ultrastructurally axonemal structure that contains a large number of proteins. A-Kinase Anchoring Protein 3 (AKAP3) is expressed in spermatozoa. It may function as a regulator of motility and the acrosome reaction. This study aimed to compare genetic changes in infertile men suffering MMAF phenotype with the control group. MATERIALS AND METHODS: In this case-control study, genetic variants of the AKAP3 gene were evaluated in 60 infertile men with MMAF phenotype and 40 fertile men, as control. As exon five of the AKAP3 gene encodes the functional domain of this protein, its genetic variants were studied. Therefore, polymerase chain reaction (PCR)-sequencing was undertaken on the DNA extracted from control and patients' blood samples. RESULTS: Sixty infertile men with MMAF phenotype and 40 normozoospermic men, as control, were enrolled in this study. Four haplotype variants 1378T>C (rs10774251), 1391C>G (rs11063266), 1437T>C (rs11063265), and 1573G>A (rs1990312) were detected in all patients and controls. On the other hand, a missense mutation 1499T>C (rs12366671) was observed in four patients with the homozygous form while seven patients carried the heterozygous form. No mutation was identified in the controls (P=0.04). The difference between the variation allele frequencies was assessed in the patient and control groups by the Fisher Exact Test. CONCLUSION: In the homozygous form, this mutation changed Isoleucine to Threonine. This alternation occurred inside the AKAP4 binding domain of the AKAP3 protein. The observed variants caused no significant deviation in the secondary structure of AKAP3 protein and probably its function in spermatozoa flagella. So, these variants cannot be considered as the causes of MMAF phenotype in the studied patients.
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Trisomy 17 is a rare chromosomal disorder. Existing literature on the topic is limited and mostly refer to mosaic Trisomy 17 cases. Our report summarizes the 70-day clinical course of a late preterm neonate with partial Trisomy 17p karyotype 46,XY,der(14)t(14;17)(p11.1;p11.2) dpat. Trisomy 17 due to unbalanced translocation is rare, and our case elaborates the clinical presentation with intestinal malfunction without any anatomical pathology and urethral diverticulum and the ethical dilemma in decision-making. The male proband was born at 35 weeks with antenatal findings of multiple neurological and other abnormalities such as cystic hygroma, absent corpus collosum, high riding third ventricle, absent cavum septum pellucidum, indented occiput, absent ductus venous, and intrauterine growth restriction. The postnatal findings included significant facial dysmorphisms with short palpebral fissures, hypertelorism, low set ears, micrognathia, hirsutism, and single palmar creases, central hypotonia, and hyperreflexia of upper limbs bilaterally. Genital-urinary assessment revealed a urinary diverticulum and significantly underdeveloped scrotum with undescended testes. Infant had excessive irritability and resistance to sleep despite increasing doses of analgesia and sedation, and persistent respiratory and feeding difficulties. Enteral nutrition could not be established due to profuse and persistent diarrhea, necessitating use of total parenteral nutrition. Microarray assay exhibited a pathogenic copy number gain of approximately 21.4 Mb of chromosome region 17p13.3p11.2. Follow-up chromosome analysis and FISH revealed an abnormal male karyotype with a derivative chromosome 14, resulting from an unbalanced translocation between the short arm of one chromosome 14 and the short arm of one chromosome 17, effectively resulting in trisomy 17p11.2. It was derived from a paternal balanced t(14;17)(p11.1;p11.2) as shown by chromosome analysis and FISH studies. The rarity of this chromosomal disorder contributed to difficulty with prognosis and led to bioethical dilemma regarding life-sustaining measures and quality of life. Through shared decision-making processes and in consideration of poor prognosis, parents decided to withdraw life-sustaining care and the proband died at postnatal day of life 70.
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Sperm structural and functi onal defects are leading causes of male infertility. Patients with immotile sperm disorders suffer from axoneme failure and show a significant reduction in sperm count. The kinesin family member 3B (KIF3B) is one of the genes involved in the proper formation of sperm with a critical role in intraflagellar and intramanchette transport. A part of exon 2 and exons 3-5 of the KIF3B encodes a protein coiled-coil domain that interacts with intraflagellar transport 20 (IFT20) from the intraflagellar transport protein complex. In the present study, the coding region of KIF3B coiled-coil domain was assessed in 88 oligoasthenoteratozoospermic (OAT) patients, and the protein expression was evaluated in the mature spermatozoa of the case and control groups using immunocytochemistry and western blotting. According to the results, there was no genetic variation in the exons 3-5 of the KIF3B, but a new A>T variant was identified within the exon 2 in 30 patients, where nothing was detected in the control group. In contrast to healthy individuals, significantly reduced protein expression was observable in oligoasthenoteratozoospermic patients carrying variation where protein organization was disarranged, especially in the principal piece and midpiece of the sperm tail. Besides, the protein expression level was lower in the patients' samples compared to that of the control group. According to the results of the present study the KIF3B gene variation as well as lower protein expression leads to defects in sperm morphology and motility and consequently to male infertility.
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Infertilidade Masculina , Cinesinas , Espermatozoides , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Cinesinas/genética , Masculino , Proteínas/metabolismo , Cauda do Espermatozoide , Espermatogênese , Espermatozoides/patologiaRESUMO
This research aimed to retrospectively investigate the possible association between poor ovarian stimulation and selected thrombophilia markers in Iranian women with infertility. For this study 100 Iranian infertile women, with a history of at least three Assisted Reproduction Technology (ART) failures (50 with a poor ovarian response and 50 with a normal response), referred to Royan Institute were selected. Targeted genetic variation evaluation for Factor V G1691A, F II Prothrombin G20210A, MTHFR C677T, MTHFR A1298C was performed by PCR-RFLP followed by Sanger Sequencing. The association between these variants and the ovarian response was examined. The results showed an association between Factor V G1691A mutation and poor ovarian response. The heterozygosity rate of the FVL was significantly different between poor responders compared with the normal response group (p-value ≤ 0.05). In conclusion screening of this polymorphism can be used as a genetic determinant of ovarian response functioning through a vascular mechanism. A larger study with bigger sample size is recommended.Impact statementWhat is already known on this subject? Thrombophilia is a multi-genetic disease that is associated with changes in homeostatic mechanisms. Some studies have suggested that thrombophilia has no relationship with poor ovarian response and reduced ovarian reserve in general infertile population undergoing ART.What do the results of this study add? Our results showed a significant association between the FVL heterozygote mutation and poor ovarian response.What are the implications of these findings for clinical practice and/or further research? Screening of FVL polymorphism may be suggested as a predictive test for ovarian stimulation response in infertile women undergoing ART. Further prospective studies with bigger sample size evaluating other thrombophilia markers and ovarian response, as well as further in-vitro studies may help clarify the biological mechanisms behind the effect of the FVL polymorphism on ovarian response, oocyte quality and embryo quality.
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Infertilidade Feminina/genética , Reserva Ovariana/genética , Indução da Ovulação/estatística & dados numéricos , Técnicas de Reprodução Assistida , Trombofilia/genética , Adulto , Estudos de Casos e Controles , Fator V/genética , Feminino , Heterozigoto , Humanos , Irã (Geográfico) , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Protrombina/genética , Estudos RetrospectivosRESUMO
BACKGROUND: Endometriosis is a prevalent gynecological disease which can lead to certain types of cancers. We investigated the spontaneous and induced chromosomal aberrations in peripheral blood lymphocytes (PBL) of endometriosis patients. METHODS: We performed a pilot study utilizing mitomycin C (MMC) to assess chromosomal instability in the peripheral blood of participants. The patient group consisted of 20 infertile endometriosis patients and the controls of 20 healthy fertile women. Blood samples were collected, and two distinct lymphocyte cultures were prepared to evaluate the baseline and the MMC induced chromosomal aberrations. RESULTS: The results showed a significant difference before and after MMC treatment in both groups (P<0.001) and also revealed that endometriosis patients are far more sensitive to MMC than controls (P<0.001). CONCLUSIONS: The significantly higher frequency of induced and spontaneous chromosomal aberrations in patients can be consider as a sign of genomic instability and the defect in DNA repair mechanisms, which can be both assumed as a driver of cancer development in endometriosis patients.
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Endometriose , Aberrações Cromossômicas , Reparo do DNA , Endometriose/genética , Feminino , Instabilidade Genômica , Humanos , Projetos PilotoRESUMO
Intracytoplasmic sperm injection (ICSI) is increasingly used to treat male-factor infertility when sperm parameters are not proper for intrauterine insemination (IUI) or in vitro fertilization (IVF). Among sperm abnormalities, short tail sperm defect is a rare kind of teratozoospermia, which is a severe cause of male infertility. In this study, we evaluated the ICSI outcomes of infertile men with severely short tail sperm defect. 117 infertile men with primary infertility were included in this study. We evaluated the impact of short tail sperm defect on large ICSI series (228 cycles) outcomes. The fertilisation rate (FR) was 49.0%, the clinical pregnancy rate (PR) was 21.7%, and the delivery rate (DR) was 17.5%. The results of statistical analysis show that there is no relationship between short tail sperm defect and clinical pregnancy. According to the present study, there were patients with successful ICSI outcomes despite the severe defect in their spermatozoa flagella. Our results can be considered in two main aspects: (a) it seems that ICSI could be a proper therapy for infertile men with short-tailed sperm defect and (b) the abnormal sperm morphology (especially in sperm flagellum) is not a reliable predictor for the ICSI outcomes. In conclusion, our study suggests that ICSI should be considered as a proper treatment way for infertile men with severe short tail sperm defect and probably other sperm flagella abnormalities.
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Infertilidade Masculina , Injeções de Esperma Intracitoplásmicas , Feminino , Fertilização in vitro , Humanos , Infertilidade Masculina/terapia , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , EspermatozoidesRESUMO
OBJECTIVE: In vitro fertilization (IVF) is one of the most efficient approaches within the context of assisted reproductive technology (ART) to treat infertility. High pregnancy rates have become the major index of successful IVF in clinical studies. It is not clear yet which factors are certainly responsible for IVF success, as various outcomes were obtained in different IVF centers with different settings. In this study, we aimed to address controversies in the interpretation of promising results of IVF with respect to preimplantation genetic screening (PGS). MATERIALS AND METHODS: In this retrospective case series study, we built a dataset containing data from 213 IVF patient candidates for PGS (654 embryos) with blastomere biopsy at day 3 and trophectoderm biopsy in day 5, referred to Royan Institute, Tehran, Iran from 2015 to 2018. Next, the data were analyzed to find influential factors affecting success rate of ART cycles. RESULTS: Data analyses showed that regardless of PGS indications (ART failures, recurrent miscarriage, chromosomal abnormalities, etc.), the pregnancy rate is influenced by maternal and embryonic factors such as the age of mother as well as quantity and quality of transferred embryos. Furthermore, genotyping of embryos using array comparative genomic hybridization (aCGH) depicted the highest rate of chromosomal aberrations for chromosomes 1, 16 and 19 while the lowest frequency for chromosomes 11 and 17. Similarly, we detected 463 genetically abnormal embryos by aCGH, among which only 41.9% could be detected by classical fluorescent in situ hybridization (FISH) method. CONCLUSION: This study not only highlighted the advantages of aCGH over the FISH method in detection of chromosomal abnormalities, but also emphasized the importance of genetic abnormality as an indication for determination of IVF success rate.
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The prevalence of infertility is increasing and worrisome. About 10 to 30% of infertility is classified as idiopathic or unexplained infertility (UI).TGF-ß is multifunctional and immunoregulatry cytokine which regulates both implantation and adhesion of trophoblasts to the extracellular matrix during pregnancy. The aim of the current study was to investigate the association between two polymorphisms rs1800470 (C29T) and rs1800471 (G74C) of the TGF-ß1 gene in Iranian patients with unexplained infertility. A total of 250 UI patients and 484 healthy individuals with no history of infertility were included in the study. The amplification and sequencing of target DNA fragments were done using PCR and automated sequencing methods, respectively. The effects of these polymorphisms on both TGF-ß1 structure and function of mRNA and protein were analyzed using new in-silico tools. The frequency distribution of the alleles, genotypes, and haplotypes of both rs1800470 and rs1800471 polymorphisms had a statistically significant difference between subjects and controls. CC genotype of TGF-ß1 rs1800470 (29CâT) increase the risk of UI in male UI patients. Moreover, C alleles of TGF-ß1 rs1800471 was associated with increased risk of UI in female UI patients. Couples, subgroup analysis revealed a significant association between TGF-ß1 polymorphisms (rs1800470, rs1800471) and the risk of UI in male, female, and all UI patients. The frequency of TG and CG haplotypes were statistically different in both UI and healthy subjects group (P < 0.05). RS1800471 polymorphisms changed the secondary structure of TGF-ß1 mRNA and resulted in the removal of one mRNA arm and creation of two new arms. Taken together, the results of the current study suggest that TGF-ß1 functional polymorphisms may play an important role in the susceptibility to UI in Iranian population. According to in silico analysis, polymorphisms in TGF-ß1 can reduce mRNA half-life and, therefore, reduced TGF-ß1 expression. .
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Infertilidade/genética , Polimorfismo de Nucleotídeo Único , Fator de Crescimento Transformador beta1/genética , Adulto , Alelos , Estudos de Casos e Controles , Simulação por Computador , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Haplótipos , Humanos , Irã (Geográfico) , Masculino , Análise de Sequência de DNA , Relação Estrutura-Atividade , Fator de Crescimento Transformador beta1/químicaRESUMO
Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene SRY is present in many cases, the etiology is unknown in most SRY-negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families (P = 4.4 × 10-6), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations (P < 1.8 × 10-4). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and Wt1Arg495Gly/Arg495Gly XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor ß-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.
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Transtornos Testiculares 46, XX do Desenvolvimento Sexual/metabolismo , Testículo/metabolismo , Proteínas WT1/metabolismo , Transtornos Testiculares 46, XX do Desenvolvimento Sexual/genética , Transtornos Testiculares 46, XX do Desenvolvimento Sexual/patologia , Animais , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Camundongos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/patologia , Proteínas WT1/química , Proteínas WT1/genética , Dedos de Zinco , beta Catenina/genética , beta Catenina/metabolismoRESUMO
The dpy-19 like 2 (DPY19L2) gene is the most common genetic cause of globozoospermia characterised by the production of round-headed spermatozoa without an acrosome. The present study was performed on 63 men with globozoospermia and 41 normozoospermic individuals to evaluate the frequency of the DPY19L2 gene and exons; deletion and genetic changes in exons 1, 5, 7-11, 19, 21 and interval introns; and some epidemiological factors (e.g. varicocele, smoking, drug use, alcohol consumption and a family history of infertility). Homozygous deletion of DPY19L2 was identified in 35% of men with globozoospermia. Exon 7 was deleted in 4.8% of men with globozoospermia in which DPY19L2 was not deleted. No genetic variations were observed within the DPY19L2 exons examined, but five intronic polymorphisms were detected: 1054-77T>C in intron 9, 1131+65T>C and 1131+53A>G in intron 10 and 1218+22T>C and 1218+73T>C in intron 11. There were significant differences in the frequency of 1054-77T>C and 1218+22T>C polymorphisms between the globozoospermic and normozoospermic groups. In addition, there were significant differences between the two groups in sperm count, sperm motility, a history of infertility in the family and varicocele. Based on these findings, DPY19L2 deletion is the major cause of total globozoospermia and there is no association between exons 1, 5, 8-11, 19 and 21 polymorphisms of the DPY19L2 gene in the occurrence of this defect.
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HIST1H1T encodes H1T, a testicular variant of histone H1, which is expressed during spermatogenesis especially in primary spermatocytes and facilitates histone to protamine exchanges during maturation of spermatozoa. The goal of the conducted research was to evaluate four genetic variations of HIST1H1T in men with nonobstructive azoospermia. This case-control study was conducted among a total number of 200 men, including 100 nonobstructive azoospermic (NOA) infertile men. In this study, three single-nucleotide polymorphisms, including c.-54C>T (rs72834678), c.-912A>C (rs707892) and c.-947A>G (rs74293938) in regulatory region as well as one SNP c.40G>C (rs198844) in coding region were identified using PCR sequencing. According to statistical analysis, none of those SNPs in regulatory regions showed significant differences in case and control groups. For SNP (c.40G>C), a significantly higher frequency of C allele in the case group was observed compared to the control group (p-value: .044). In conclusion, according to statistical analysis it seems that the polymorphism of c.40G>C is not associated with nonobstructive azoospermia.
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Azoospermia , Histonas , Azoospermia/genética , Estudos de Casos e Controles , Humanos , Masculino , Sequências Reguladoras de Ácido Nucleico , Espermatogênese/genéticaRESUMO
The dpy-19 like 2 (DPY19L2) gene is the most common genetic cause of globozoospermia characterised by the production of round-headed spermatozoa without an acrosome. The present study was performed on 63 men with globozoospermia and 41 normozoospermic individuals to evaluate the frequency of the DPY19L2 gene and exons; deletion and genetic changes in exons 1, 5, 7-11, 19, 21 and interval introns; and some epidemiological factors (e.g. varicocele, smoking, drug use, alcohol consumption and a family history of infertility). Homozygous deletion of DPY19L2 was identified in 35% of men with globozoospermia. Exon 7 was deleted in 4.8% of men with globozoospermia in which DPY19L2 was not deleted. No genetic variations were observed within the DPY19L2 exons examined, but five intronic polymorphisms were detected: 1054-77T>C in intron 9, 1131+65T>C and 1131+53A>G in intron 10 and 1218+22T>C and 1218+73T>C in intron 11. There were significant differences in the frequency of 1054-77T>C and 1218+22T>C polymorphisms between the globozoospermic and normozoospermic groups. In addition, there were significant differences between the two groups in sperm count, sperm motility, a history of infertility in the family and varicocele. Based on these findings, DPY19L2 deletion is the major cause of total globozoospermia and there is no association between exons 1, 5, 8-11, 19 and 21 polymorphisms of the DPY19L2 gene in the occurrence of this defect.
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Deleção de Genes , Infertilidade Masculina/genética , Proteínas de Membrana/genética , Teratozoospermia/genética , Éxons/genética , Frequência do Gene , Predisposição Genética para Doença , Variação Genética/genética , Homozigoto , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Polimorfismo Genético/genética , Análise de Sequência de DNA , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Teratozoospermia/epidemiologia , Varicocele/epidemiologiaRESUMO
SEPT12 is a testis-specific gene involved in the terminal differentiation of male germ cells. SEPT12 protein is required for sperm head-tail formation and acts as a fundamental constituent of sperm tail annulus. In this study, we screened genetic variations in exons 5, 6, 7 of the SEPT12 and assessed the annulus status in teratozoospermic, globozoospermic, and patients with immotile short tail sperm. DNA sequencing was performed for 90 teratozoospermic and 30 normozoospermic individuals. Immunocytochemistry, transmission electron microscopy and western blotting were conducted to evaluate annulus status and the expression level of SEPT12 in patients with a distinct exonic variation (c.474G>A), respectively. Five polymorphisms identified within the desired regions of the SEPT12, among them c.474G>A had the potential to induce aberrant splicing results in the expression of a truncated protein. The annulus was detected in most of the spermatozoa from teratozoospermic and normozoospermic men with c.474G>A. In contrast, in the patient with short tail sperm defect carrying c.474G>A, 99% of spermatozoa were devoid of the annulus. Based on our findings there would be no association between exons 5, 6, 7 polymorphisms of the SEPT12 gene and the occurrence of mentioned disease but c.474G>A would be a predisposing factor in male infertility.
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Éxons , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Septinas/genética , Teratozoospermia/genética , Estudos de Casos e Controles , Causalidade , Estudos de Coortes , Humanos , Íntrons , Irã (Geográfico)/epidemiologia , Masculino , Cauda do Espermatozoide/metabolismo , Teratozoospermia/epidemiologia , Testículo/metabolismoRESUMO
Teratozoospermia is characterised by the presence of spermatozoa with abnormal morphology. One of the morphological disorders that lead to male infertility is immotile short-tail sperm (ISTS) defect. In this study, we evaluated the levels of chromatin packing and DNA fragmentation in patients with immotile short-tail sperm defect. Semen samples were obtained from 31 infertile men with ISTS as case group and 31 normozoospermic men as a control group. Protamine status was evaluated using chromomycin A3 (CMA3) staining and sperm DNA fragmentation assessed by sperm chromatin structure assay (SCSA) and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick-end labelling (TUNEL). The percentage of positive CMA3 spermatozoa was significantly higher in patients' samples (22.6 ± 6.9) compared with controls (16.3 ± 4.2) (p < .05) and also mean (±SD) of sperm DNA fragmentation was significantly higher in patients compared with controls, as measured by TUNEL assay (10.45 ± 4.60 vs. 7.03 ± 2.86, p < .05) and SCSA (24.80 ± 13.1 vs. 15.2 ± 7.2, p < .05). According to our study, sperm DNA fragmentation and chromatin packing abnormality are significantly higher in the ISTS samples compared with normal samples. A possible explanation for this relationship is that sperm chromatin condensation and sperm flagellum formation occur during the same phase of spermatogenesis.
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Cromatina/metabolismo , Fragmentação do DNA , Cauda do Espermatozoide/patologia , Teratozoospermia/genética , Adulto , Estudos de Casos e Controles , Cromomicina A3/química , Empacotamento do DNA , Corantes Fluorescentes/química , Humanos , Masculino , Pessoa de Meia-Idade , Teste de Papanicolaou , Protaminas/metabolismo , Análise do Sêmen/métodos , Cauda do Espermatozoide/metabolismo , Teratozoospermia/patologia , Adulto JovemRESUMO
Androgens play a key role in spermatogenesis, and their functions are mediated by the androgen receptor (AR). Some mutations in the AR gene have the potential to alter the primary structure and function of the protein. The aim of this study was to investigate the AR gene mutations in a cohort of males with idiopathic azoospermia referred to Royan Institute. Fifty-one biopsy samples were obtained for routine clinical purposes from 15 men with hypospermatogenesis (HS), 17 patients with maturation arrest (MA) and 19 patients with Sertoli cell-only syndrome (SCOS). The AR cDNAs were prepared from tissue mRNAs and were sequenced. One synonymous variant and three nonsynonymous protein coding single nucleotide polymorphisms (nsSNPs) were detected. Protein structure prediction demonstrated that the S815I and M746T nonsynonymous variants would affect protein structure and its normal function. Our study suggests that mutations in the AR gene would change or disturb the receptor's normal activity. Although these variations may influence spermatogenesis, it is difficult to say that they lead to a lack of spermatogenesis.
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Azoospermia/congênito , Oligospermia/genética , Receptores Androgênicos/genética , Síndrome de Células de Sertoli/genética , Espermatogênese/genética , Adulto , Azoospermia/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Domínios Proteicos/genéticaRESUMO
Obstructive azoospermia (OA), defined as an obstruction in any region of the male genital tract, accounts for 40% of all azoospermia cases. Of all OA cases, ~30% are thought to have a genetic origin, however, hitherto, the underlying genetic etiology of the majority of these cases remain unknown. To address this, we took a family-based whole-exome sequencing approach to identify causal variants of OA in a multiplex family with epidydimal obstruction. A novel gain-of-function missense variant in CLDN2 (c.481G>C; p.Gly161Arg) was found to co-segregate with the phenotype, consistent with the X-linked inheritance pattern observed in the pedigree. To assess the pathogenicity of this variant, the wild and mutant protein structures were modeled and their potential for strand formation in multimeric form was assessed and compared. The results showed that dimeric and tetrameric arrangements of Claudin-2 were not only reduced, but were also significantly altered by this single residue change. We, therefore, envisage that this amino acid change likely forms a polymeric discontinuous strand, which may lead to the disruption of tight junctions among epithelial cells. This missense variant is thus likely to be responsible for the disruption of the blood-epididymis barrier, causing dislodged epithelial cells to clog the genital tract, hence causing OA. This study not only sheds light on the underlying pathobiology of OA, but also provides a basis for more efficient diagnosis in the clinical setting.
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Azoospermia/genética , Claudinas/genética , Mutação de Sentido Incorreto , Azoospermia/diagnóstico por imagem , Azoospermia/etiologia , Azoospermia/patologia , Claudinas/química , Família , Humanos , Masculino , Modelos Moleculares , Linhagem , Fenótipo , Sequenciamento do ExomaRESUMO
Hypogonadotropic hypogonadism (HH) is defined as a dysfunction of hypothalamic-pituitary-gonadal axis, which causes impairments in gametogenesis, pubertal maturation, and/or secretion of the gonadal sex hormones. Human chronic gonadotropin (hCG) stimulates the Leydig cells of the testis to secrete testosterone, which is essential for spermatogenesis. Testosterone replacement therapy is one of the possible options to manage HH treatment. Given the fact that testosterone functions are mediated via androgen receptor (AR), the aim of the present study was to evaluate whether the CAG/GGN triple repeat expansion in AR gene can modulate the response to hCG and testosterone treatment in HH men. Sixty-two men who diagnosed with HH and treated with testosterone and hCG were assessed after treatment. They were classified into two groups, 31 subjects with a positive and 31 subjects with a negative response to replacement therapy within 12-18 months. Androgen receptor CAG and GGN repeat numbers were measured in both groups by hot start polymerase chain reaction (PCR)-sequencing technique. Subjects who reached complete spermatogenesis showed the 20 and 23 as the median numbers of AR CAG/GGN repeats, respectively. In individuals who did not respond to treatment the median length for both CAG/GGN repeats were 23. The average of CAG repeats was statistically lower in patients who had the positive response in comparison to patients who did not respond to hormone therapy (p < 0.05), but the length of GGN repeats were not statistically different between these groups of patients (p > 0.05). The number of CAG repeats are negatively and signiï¬cantly associated with better hormone therapy response. Our results suggest that the length of CAG repeat polymorphism in AR gene might affect the response to treatment in men suffering from HH, whereas no relationship was found between AR gene GGN repeat polymorphism and testosterone and hCG replacement therapy response. Abbreviations: AR: androgen receptor; FSH: follicle stimulating hormone; Gn: gonadotropins; GnRH: gonadotropin-releasing hormone; hCG: human chronic gonadotropin; HH: hypogonadotropic hypogonadism; LH: luteinizing hormone; PCR: polymerase chain reaction.
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Gonadotropina Coriônica/uso terapêutico , Hipogonadismo/genética , Infertilidade Masculina/genética , Receptores Androgênicos/genética , Testosterona/uso terapêutico , Adulto , Humanos , Hipogonadismo/complicações , Infertilidade Masculina/complicações , Infertilidade Masculina/tratamento farmacológico , Masculino , Repetições de Microssatélites , Espermatogênese/efeitos dos fármacos , Espermatogênese/genética , Resultado do Tratamento , Adulto JovemRESUMO
47,XYY syndrome is a sex chromosomal anomaly in men, which may be associated with infertility and has an incidence of 0.1% of male births. The clinical and paraclinical characteristics of men suffering from this anomaly have not been fully described. In this retrospective study, we present 37 cases of 47,XYY infertile men with sperm counts varying from normal to azoospermia, referred to the Genetics Laboratory at the Royan Institute, Iran. Thirteen individuals were mosaic and 24 non-mosaics. Non-mosaic patients were classified as azoospermic (nine cases) and normospermic/oligozoospermic men (15 cases). Two of the non-mosaic and three mosaic patients had secondary infertility. In addition, 13 of them underwent IUI, IVF or ICSI, and in seven cases, there was a biochemical pregnancy. The remaining 14 patients did not have ART. The 47,XYY syndrome is relatively unusual and can be missed clinically because of the lack of symptoms and of diverse phenotypes. Diagnosis of this aneuploidy can provide valuable data for counselling and early management of the patients who undergo fertility evaluation.
Assuntos
Infertilidade Masculina/genética , Mosaicismo , Cariótipo XYY , Adulto , Humanos , Infertilidade Masculina/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doenças Testiculares/etiologiaRESUMO
Genetic abnormalities have been considered a significant cause of male infertility. Increased expression of SPATA33 during the first wave of spermatogenesis indicates its possible association with the meiotic process. The aim of the current study was to investigate the genetic variations in the SPATA33 gene and its expression in patients with nonobstructive azoospermia (NOA). A total of 100 Iranian NOA men with idiopathic infertility were taken as the case group. The control group comprised 100 fertile men who had at least one child. The presence of nucleotide variations was analyzed in both groups using the standard polymerase chain reaction (PCR) sequencing technique. For mRNA and protein expression studies, testicular biopsy specimens from 27 patients were subdivided into three groups: nine obstructive azoospermic patients with hypospermatogenesis as control; nine maturation arrest (MA) and nine Sertoli cell-only syndromes (SCOS) as case groups. The expression of SPATA33 at both mRNA and protein levels was compared among these three groups using the reverse transcription PCR technique, the realtime-PCR technique, and immunohistochemistry. Mutation analysis of the SPATA33 gene revealed five nucleotide changes among the population studied. All but one showed no significant differences between the groups. The genotype distributions of rs112536073A > T in the transcription factor binding site region with heterozygote and homozygote genotypes were significantly different ( p < 0.05) between the two groups. More heterozygotes of this polymorphism were observed in patients, whereas more homozygotes were detected in controls. Accordingly, the current study illustrated that alterations in SPATA33 gene, at least those found in this study, may not impair spermatogenesis in patients with NOA. Reduction of gene expression at the level of mRNA in patients with SCOS can be interpreted by the absence of germ cells in the testicular tissue of these patients.
Assuntos
Azoospermia/metabolismo , Regulação da Expressão Gênica , Oligospermia/metabolismo , Testículo/metabolismo , Adulto , Idoso , Azoospermia/genética , Azoospermia/patologia , Biópsia , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Oligospermia/genética , Oligospermia/patologia , Reação em Cadeia da Polimerase em Tempo Real , Elementos de Resposta , Testículo/patologiaRESUMO
Androgen receptor (AR) mediates androgen activities such as the growth of accessory sex organs, and initiation and promotion of spermatogenesis. There are two trinucleotide polymorphisms (CAG and GGN repeats) in the first exon of AR gene that their association with infertility is still controversial. The variants of both polymorphic repeats were investigated by PCR-Sequencing in 220 infertile men (80 azoospermic, 60 oligospermic and 80 asthenospermic) and 80 healthy fertile controls. AR Expression level was quantified by RT-qPCR on 30 patients (20 patients with nonobstructive azoospermia (NOA) and 10 obstructive azoospermia patients as controls). Our results demonstrated that the medians of CAG and GGN repeats length in infertile group were significantly higher than fertile men (p < 0.05). AR expression results showed a significant increase in SCOS group compared to control (p < 0.05). Long stretches of tandem repeats of AR gene may negatively affect the function of the gene and consequently lead to male infertility. In patients with SCOS, AR expression increases because of the lack of germ cells. Therefore, with increasing AR expression, the probability of SCOS occurrence is also increased. It can be concluded that increasing AR expression in testes tissue decreases the probability of sperm presence.