RESUMO
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.
Assuntos
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
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.
Assuntos
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.
Assuntos
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
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.
Assuntos
Infertilidade Masculina , Injeções de Esperma Intracitoplásmicas , Feminino , Fertilização in vitro , Humanos , Infertilidade Masculina/terapia , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , EspermatozoidesRESUMO
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.
Assuntos
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
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.
Assuntos
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
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.
RESUMO
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.
Assuntos
Azoospermia , Histonas , Azoospermia/genética , Estudos de Casos e Controles , Humanos , Masculino , Sequências Reguladoras de Ácido Nucleico , Espermatogênese/genéticaRESUMO
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.
Assuntos
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
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.
Assuntos
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
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.
Assuntos
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
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
Ring chromosome 15 [r(15)] is a rare condition with a mild-to-severe growth failure, mental disabilities, café-au-lait spots, specific facial features, fertility difficulties and other minor dysmorphic stigmata. Of almost 50 affected individuals reported in the literature, none were assessed for the precise breakpoint positioning, which creates uncertainty in defining a specific phenotype for the deleted segment. This study reports for the first time the vertical transmission of r(15) in three consecutive generations of a family, including a subfertile man, his mother and his newborn infant. Array comparative genomic hybridization results revealed a 563 kb deletion of 15q26.3, overlapping the OMIM genes SNRP1, PCSK6 and TM2D3. The hemizygosity was confirmed with real-time quantitative PCR. Regarding haploinsufficiency in 15q26.3, based on phenotypic characteristics of the carriers, the only rational conclusion is that SNRPA1, PCSK6 and TM2D3 are not gene-dosage sensitive and are probably inherited in an autosomal-recessive manner. Given growth deficiency in r(15) carriers, this shows that the growth retardation cannot be attributed entirely to IGF1R. The predominance of female patients with r(15) is the next as yet unanswered question; incomplete penetrance and/or variable expression of gene(s) in different genders may be involved, but further evidence is needed to support this idea.
Assuntos
Infertilidade Masculina/genética , Padrões de Herança , Cromossomos em Anel , Adulto , Idoso , Cromossomos Humanos Par 15 , Feminino , Humanos , Recém-Nascido , Cariotipagem , Masculino , MosaicismoRESUMO
To evaluate the success rate in sperm retrieval (SR) through microdissection testicular sperm extraction (micro-TESE) in infertile azoospermia factor c (AZFc)-deleted men and determining their reproductive outcomes following ICSI, medical records of couples with AZFc-deleted male partners were reviewed on patient's age, serum hormone levels, karyotype, testicular pathology and pregnancy outcomes. A comparison on age and serum hormone level was conducted between groups with positive and negative sperm retrieval in both azoospermic and oligozoospermic AZFc-deleted men. Of 225 who had AZFc deletion, 195 cases followed clinical treatments. From 195 cases, 116 were azoospermic, 79 were oligozoospermic. Pathology profile was available in 103 of 195 subjects which the predominant trait was SCOS and was seen in 66.9% of cases (69 of 103). Success rate of sperm retrieval in azoospermic patients who underwent micro-TESE was 36.3% (28/77). Forty-three oligozoospermic and 17 azoospermic patients started ART cycle. Pregnancy rate in oligozoospermic group was 35.4% (17 cases), whilst there was no clinical pregnancy in azoospermic group. In conclusion, the pregnancy and delivery in oligozoospermic patients with AZFc deletion are comparable with other studies, but despite of sperm retrieval in azoospermic patients with AZFc deletion, the chance of pregnancy or delivery in these patients was very low.
Assuntos
Azoospermia/terapia , Cromossomos Humanos Y/genética , Oligospermia/terapia , Recuperação Espermática , Adulto , Idoso , Azoospermia/genética , Feminino , Humanos , Irã (Geográfico) , Masculino , Microdissecção , Pessoa de Meia-Idade , Oligospermia/genética , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Testículo/cirurgia , Resultado do Tratamento , Adulto JovemRESUMO
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.
Assuntos
Astenozoospermia/genética , Azoospermia/genética , Oligospermia/genética , Receptores Androgênicos/genética , Síndrome de Células de Sertoli/genética , Adulto , Azoospermia/patologia , Estudos de Casos e Controles , Voluntários Saudáveis , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Receptores Androgênicos/metabolismo , Síndrome de Células de Sertoli/epidemiologia , Síndrome de Células de Sertoli/patologia , Contagem de Espermatozoides , Testículo/patologia , Repetições de Trinucleotídeos/genéticaRESUMO
Recurrent pregnancy loss (RPL) is an important clinical problem, mostly resulting from chromosomal or genetic defects, while in 30-60% of cases, it is idiopathic. The aim of this study is to evaluate the frequency and types of chromosomal abnormalities, also pre-implantation genetic diagnosis (PGD) and pre-implantation genetic screening (PGS) outcomes among Iranian couples with RPL. This retrospective study was conducted on 1100 Iranian couples (2200 individuals) with RPL referred to Royan Institute between 2008 and 2014. Karyotyping had been performed using standard cytogenetic techniques. PGD results of RPL patients with abnormal karyotypes and PGS results of RPL patients with normal karyotypes were also analyzed. The frequency of chromosomal abnormalities in these patients was 4.95%. Women demonstrated more abnormalities (6.82%) in comparison to men (3.09%). The successful rate of pregnancy after PGD and PGS was 52 and 18.64%, respectively. The observation of 4.95% chromosomal abnormalities among the patients with RPL could support this hypothesis that there is a direct relationship between chromosomal abnormalities and RPL. More than half of the patients who underwent PGD had successful pregnancy; therefore, this approach can improve the success rate of pregnancy in them. The results of PGS cycles showed that this technique could increase the live birth rate in RPL patients.
Assuntos
Aborto Habitual/diagnóstico , Aborto Habitual/epidemiologia , Aberrações Cromossômicas/estatística & dados numéricos , Testes Genéticos/estatística & dados numéricos , Diagnóstico Pré-Implantação/estatística & dados numéricos , Adulto , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Gravidez , Taxa de GravidezRESUMO
The human Y chromosome has an inevitable role in male fertility because it contains many genes critical for spermatogenesis and the development of the male gonads. Any genetic variation or epigenetic modification affecting the expression pattern of Y chromosome genes may thus lead to male infertility. In this study, we performed isoform-level gene expression profiling of Y chromosome genes within the azoospermia factor (AZF) regions, their X chromosome counterparts, and few autosomal paralogues in testicular biopsies of 12 men with preserved spermatogenesis and 68 men with nonobstructive azoospermia (NOA) (40 Sertoli-cell-only syndrome (SCOS) and 28 premiotic maturation arrest (MA)). This was undertaken using quantitative real-time PCR (qPCR) at the transcript level and Western blotting (WB) and immunohistochemistry (IHC) at the protein level. We profiled the expression of 41 alternative transcripts encoded by 14 AZFa, AZFb, and AZFc region genes (USP9Y, DDX3Y, XKRY, HSFY1, CYORF15A, CYORF15B, KDM5D, EIF1AY, RPS4Y2, RBMY1A1, PRY, BPY2, DAZ1, and CDY1) as well as their X chromosome homologue transcripts and a few autosomal homologues. Of the 41 transcripts, 18 were significantly down-regulated in men with NOA when compared with those of men with complete spermatogenesis. In contrast, the expression of five transcripts increased significantly in NOA patients. Furthermore, to confirm the qPCR results at the protein level, we performed immunoblotting and IHC experiments (based on 24 commercial and homemade antibodies) that detected 10 AZF-encoded proteins. In addition, their localization in testis cell types and organelles was determined. Interestingly, the two missing proteins, XKRY and CYORF15A, were detected for the first time. Finally, we focused on the expression patterns of the significantly altered genes in 12 MA patients with successful sperm retrieval compared to those of 12 MA patients with failed sperm retrieval to predict the success of sperm retrieval in azoospermic men. We showed that HSFY1-1, HSFY1-3, BPY2-1, KDM5C2, RBMX2, and DAZL1 transcripts could be used as potential molecular markers to predict the presence of spermatozoa in MA patients. In this study, we have identified isoform level signature that can be used to discriminate effectively between MA, SCOS, and normal testicular tissues and suggests the possibility of diagnosing the presence of mature sperm cell in azoospermic men to prevent additional testicular sperm extraction (TESE) surgery.
Assuntos
Azoospermia/genética , Cromossomos Humanos X , Cromossomos Humanos Y , Perfilação da Expressão Gênica , Testículo/patologia , Adulto , Azoospermia/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Low doses of ionizing radiation may induce an adaptive mechanism which protects embryonic stem cells against higher doses, a phenomenon which was reported previously for somatic cells. In this study, a possible adaptive response (AR) was evaluated by measuring cell survival (MTT assay) and chromosomal aberrations (micronucleus assay). Thymidine-synchronized mouse embryonic stem cells (mESCs) were exposed to 2.5, 3.7, or 5cGy (60)Co γ-rays and, after 5h challenged by a dose of 150cGy. mESCs pre-irradiated at 2.5cGy showed an adaptive response.
Assuntos
Adaptação Biológica , Células-Tronco Embrionárias/efeitos da radiação , Raios gama/efeitos adversos , Adaptação Biológica/efeitos da radiação , Animais , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Aberrações Cromossômicas/efeitos da radiação , Relação Dose-Resposta à Radiação , Células-Tronco Embrionárias/fisiologia , Camundongos , Testes para Micronúcleos , Doses de RadiaçãoRESUMO
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.
RESUMO
The Chromosome-centric Human Proteome Project (C-HPP) aims to systematically map the entire human proteome with the intent to enhance our understanding of human biology at the cellular level. This project attempts simultaneously to establish a sound basis for the development of diagnostic, prognostic, therapeutic, and preventive medical applications. In Iran, current efforts focus on mapping the proteome of the human Y chromosome. The male-specific region of the Y chromosome (MSY) is unique in many aspects and comprises 95% of the chromosome's length. The MSY continually retains its haploid state and is full of repeated sequences. It is responsible for important biological roles such as sex determination and male fertility. Here, we present the most recent update of MSY protein-encoding genes and their association with various traits and diseases including sex determination and reversal, spermatogenesis and male infertility, cancers such as prostate cancers, sex-specific effects on the brain and behavior, and graft-versus-host disease. We also present information available from RNA sequencing, protein-protein interaction, post-translational modification of MSY protein-coding genes and their implications in biological systems. An overview of Human Y chromosome Proteome Project is presented and a systematic approach is suggested to ensure that at least one of each predicted protein-coding gene's major representative proteins will be characterized in the context of its major anatomical sites of expression, its abundance, and its functional relevance in a biological and/or medical context. There are many technical and biological issues that will need to be overcome in order to accomplish the full scale mapping.