Percorrer por autor "Nunes, Joaquim"
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- Avaliação da Frequência de Microdelecções AZF e alterações do cariótipo na OligospermiaPublication . Pereira, Isabel; Barros, Joana; Aguiar, Ana; Sousa, Sandra; Nunes, Joaquim; Rodrigues, Cátia; Soares, Ana Paula; Pereira-Caetano, Iris; Gonçalves, João; Calhaz Jorge, CarlosA infertilidade masculina é uma entidade complexa que afecta um número importante de homens, permanecendo a sua etiologia desconhecida em muitas situações. Alterações do cariótipo podem contribuir para diminuir a quantidade e qualidade dos espermatozóides. A elucidação de eventual base genética subjacente pode ajudar a determinar a razão da alteração espermática e abrir novas perspectivas para tratamentos eficazes. A região AZF (azoospermia factor) do cromossoma Y contém genes essenciais para a espermatogénese.
- AZF midrodeletions screening in infertile men of the Portuguese populationPublication . Pereira, Iris; Silva, Júlia; Correia, Sónia; Pinto, Maria Graça; Rangel, Ricardo; Aguiar, Ana; Nunes, Joaquim; Calhaz Jorge, Carlos; Gonçalves, JoãoAnalysis of genetic conditions associated with male infertility is, at present days, restricted to chromosome analysis, AZF Y-chromosome microdeletions screening, and to patients with hypogonadotrophic hypogonadism or with congenital absence of the vas deferens. Among different populations AZF microdeletions can explain 10-15% of the infertile phenotype of azoospermic men and 2-5% of oligozoospermic men. Here we present the results of AZF deletions screening performed in a selected group of infertile Portuguese men with idiopathic non-obstructive azoospermia or with oligozoospermia (men with other causes of male infertility, endocrinological alterations, varicocele, criptorquidism, professional risk factors, autosomal chromosomal abnormalities, were excluded for this study). Analysis was performed by Multiplex-PCR using specific STS for the three AZF regions. Microdeletion breakpoints were confirmed using a second multiplex-PCR. We analysed 865 infertile men (270 azospermic and 595 oligozoospermic with [spermatozoa]<5x106/mL) and 300 DNA samples obtained from fertile men of the Portuguese population. While AZF microdeletions were found in 27 azoospermic (10.0%) and in 22 oligozoospermic men (3.7%), in fertile men no microdeletions were detected.Our results demonstrate that AZF microdeletions are frequent among males with the infertile phenotype described above. The regions absent have prognostic value for the clinical decision and patients treatment. Genetic counselling is recommended to all patients with AZFdel. AZFcdel will be obligatorily transmitted to all male offspring by ICSI, which will seriously impair their fertility.
- Common Variation in the PIN1 Locus Increases the Genetic Risk to Suffer from Sertoli Cell-Only SyndromePublication . Cerván-Martín, Miriam; Bossini-Castillo, Lara; Guzmán-Jimenez, Andrea; Rivera-Egea, Rocío; Garrido, Nicolás; Luján, Saturnino; Romeu, Gema; Santos-Ribeiro, Samuel; Castilla, José A.; Gonzalvo, M. Carmen; Clavero, Ana; Vicente, F. Javier; Maldonado, Vicente; González-Muñoz, Sara; Rodríguez-Martín, Inmaculada; Burgos, Miguel; Jiménez, Rafael; Pinto, Maria Graça; Pereira, Isabel; Nunes, Joaquim; Sánchez-Curbelo, Josvany; López-Rodrigo, Olga; Pereira-Caetano, Iris; Marques, Patricia Isabel; Carvalho, Filipa; Barros, Alberto; Bassas, Lluís; Seixas, Susana; Gonçalves, João; Larriba, Sara; Lopes, Alexandra M.; Carmona, F. David; Palomino-Morales, Rogelio J.We aimed to analyze the role of the common genetic variants located in the PIN1 locus, a relevant prolyl isomerase required to control the proliferation of spermatogonial stem cells and the integrity of the blood-testis barrier, in the genetic risk of developing male infertility due to a severe spermatogenic failure (SPGF). Genotyping was performed using TaqMan genotyping assays for three PIN1 taggers (rs2287839, rs2233678 and rs62105751). The study cohort included 715 males diagnosed with SPGF and classified as suffering from non-obstructive azoospermia (NOA, n = 505) or severe oligospermia (SO, n = 210), and 1058 controls from the Iberian Peninsula. The allelic frequency differences between cases and controls were analyzed by the means of logistic regression models. A subtype specific genetic association with the subset of NOA patients classified as suffering from the Sertoli cell-only (SCO) syndrome was observed with the minor alleles showing strong risk effects for this subset (ORaddrs2287839 = 1.85 (1.17-2.93), ORaddrs2233678 = 1.62 (1.11-2.36), ORaddrs62105751 = 1.43 (1.06-1.93)). The causal variants were predicted to affect the binding of key transcription factors and to produce an altered PIN1 gene expression and isoform balance. In conclusion, common non-coding single-nucleotide polymorphisms located in PIN1 increase the genetic risk to develop SCO.
- Contribution of TEX15 genetic variants to the risk of developing severe non-obstructive oligozoospermiaPublication . Guzmán-Jiménez, Andrea; González-Muñoz, Sara; Cerván-Martín, Miriam; Rivera-Egea, Rocío; Garrido, Nicolás; Luján, Saturnino; Santos-Ribeiro, Samuel; Castilla, José A.; Gonzalvo, M. Carmen; Clavero, Ana; Vicente, F. Javier; Maldonado, Vicente; Villegas-Salmerón, Javier; Burgos, Miguel; Jiménez, Rafael; Pinto, Maria Graça; Pereira, Isabel; Nunes, Joaquim; Sánchez-Curbelo, Josvany; López-Rodrigo, Olga; Pereira-Caetano, Iris; Marques, Patricia Isabel; Carvalho, Filipa; Barros, Alberto; Bassas, Lluís; Seixas, Susana; Gonçalves, João; Lopes, Alexandra M.; Larriba, Sara; Palomino-Morales, Rogelio J.; Carmona, F. David; Bossini-Castillo, LaraBackground: Severe spermatogenic failure (SPGF) represents one of the most relevant causes of male infertility. This pathological condition can lead to extreme abnormalities in the seminal sperm count, such as severe oligozoospermia (SO) or non-obstructive azoospermia (NOA). Most cases of SPGF have an unknown aetiology, and it is known that this idiopathic form of male infertility represents a complex condition. In this study, we aimed to evaluate whether common genetic variation in TEX15, which encodes a key player in spermatogenesis, is involved in the susceptibility to idiopathic SPGF. Materials and Methods: We designed a genetic association study comprising a total of 727 SPGF cases (including 527 NOA and 200 SO) and 1,058 unaffected men from the Iberian Peninsula. Following a tagging strategy, three tag single-nucleotide polymorphisms (SNPs) of TEX15 (rs1362912, rs323342, and rs323346) were selected for genotyping using TaqMan probes. Case-control association tests were then performed by logistic regression models. In silico analyses were also carried out to shed light into the putative functional implications of the studied variants. Results: A significant increase in TEX15-rs1362912 minor allele frequency (MAF) was observed in the group of SO patients (MAF = 0.0842) compared to either the control cohort (MAF = 0.0468, OR = 1.90, p = 7.47E-03) or the NOA group (MAF = 0.0472, OR = 1.83, p = 1.23E-02). The genotype distribution of the SO population was also different from those of both control (p = 1.14E-02) and NOA groups (p = 4.33–02). The analysis of functional annotations of the human genome suggested that the effect of the SO-associated TEX15 variants is likely exerted by alteration of the binding affinity of crucial transcription factors for spermatogenesis. Conclusion: Our results suggest that common variation in TEX15 is involved in the genetic predisposition to SO, thus supporting the notion of idiopathic SPGF as a complex trait.
- Immune and spermatogenesis-related loci are involved in the development of extreme patterns of male infertilityPublication . Cerván-Martín, Miriam; Tüttelmann, Frank; Lopes, Alexandra M.; Bossini-Castillo, Lara; Rivera-Egea, Rocío; Garrido, Nicolás; Lujan, Saturnino; Romeu, Gema; Santos-Ribeiro, Samuel; Castilla, José A.; Carmen Gonzalvo, M.; Clavero, Ana; Maldonado, Vicente; Vicente, F. Javier; González-Muñoz, Sara; Guzmán-Jiménez, Andrea; Burgos, Miguel; Jiménez, Rafael; Pacheco, Alberto; González, Cristina; Gómez, Susana; Amorós, David; Aguilar, Jesus; Quintana, Fernando; Calhaz-Jorge, Carlos; Aguiar, Ana; Nunes, Joaquim; Sousa, Sandra; Pereira, Isabel; Pinto, Maria Graça; Correia, Sónia; Sánchez-Curbelo, Josvany; López-Rodrigo, Olga; Martín, Javier; Pereira-Caetano, Iris; Marques, Patricia I.; Carvalho, Filipa; Barros, Alberto; Gromoll, Jörg; Bassas, Lluís; Seixas, Susana; Gonçalves, João; Larriba, Sara; Kliesch, Sabine; Palomino-Morales, Rogelio J.; Carmona, F. DavidWe conducted a genome-wide association study in a large population of infertile men due to unexplained spermatogenic failure (SPGF). More than seven million genetic variants were analysed in 1,274 SPGF cases and 1,951 unaffected controls from two independent European cohorts. Two genomic regions were associated with the most severe histological pattern of SPGF, defined by Sertoli cell-only (SCO) phenotype, namely the MHC class II gene HLA-DRB1 (rs1136759, P = 1.32E-08, OR = 1.80) and an upstream locus of VRK1 (rs115054029, P = 4.24E-08, OR = 3.14), which encodes a protein kinase involved in the regulation of spermatogenesis. The SCO-associated rs1136759 allele (G) determines a serine in the position 13 of the HLA-DRβ1 molecule located in the antigen-binding pocket. Overall, our data support the notion of unexplained SPGF as a complex trait influenced by common variation in the genome, with the SCO phenotype likely representing an immune-mediated condition.
- Intronic variation of the SOHLH2 gene confers risk to male reproductive impairmentPublication . Cerván-Martín, Miriam; Suazo-Sánchez, M. Irene; Rivera-Egea, Rocío; Garrido, Nicolás; Luján, Saturnino; Romeu, Gema; Santos-Ribeiro, Samuel; Castilla, José A.; Gonzalvo, M. Carmen; Clavero, Ana; Vicente, F. Javier; Maldonado, Vicente; Burgos, Miguel; Barrionuevo, Francisco J.; Jiménez, Rafael; Sánchez-Curbelo, Josvany; López-Rodrigo, Olga; Peraza, M. Fernanda; Pereira-Caetano, Iris; Marques, Patricia I.; Carvalho, Filipa; Barros, Alberto; Bassas, Lluís; Seixas, Susana; Gonçalves, João; Larriba, Sara; Lopes, Alexandra M.; Palomino-Morales, Rogelio J.; Carmona, F. David; Calhaz-Jorge, Carlos; Aguiar, Ana; Nunes, Joaquim; Sousa, Sandra; Graça Pinto, Maria; Correia, Sónia; Pacheco, Alberto; González, Cristina; Gómez, Susana; Amorós, David; Aguilar, Jesús; Quintana, FernandoObjective: To evaluate whether SOHLH2 intronic variation contributes to the genetic predisposition to male infertility traits, including severe oligospermia (SO) and different nonobstructive azoospermia (NOA) clinical phenotypes. Design: Genetic association study. Setting: Not applicable. Patient(s): Five hundred five cases (455 infertile patients diagnosed with NOA and 50 with SO) and 1,050 healthy controls from Spain and Portugal. Intervention(s): None. Main outcome measure(s): Genomic DNA extraction from peripheral blood mononuclear cells, genotyping of the SOHLH2 polymorphisms rs1328626 and rs6563386 using the TaqMan allelic discrimination technology, case-control association analyses using logistic regression models, and exploration of functional annotations in publicly available databases. Result(s): Evidence of association was observed for both rs6563386 with SO and rs1328626 with unsuccessful sperm retrieval after testicular sperm extraction (TESE-) in the context of NOA. A dominant effect of the minor alleles was suggested in both associations, either when the subset of patients with the manifestation were compared against the control group (rs6563386/SO: P=.021, odds ratio [OR] = 0.51; rs1328626/TESE-: P=.066, OR = 1.46) or against the group of patients without the manifestation (rs6563386/SO: P=.014, OR = 0.46; rs1328626/TESE-: P=.012, OR = 2.43). The haplotype tests suggested a combined effect of both polymorphisms. In silico analyses evidenced that this effect could be due to alteration of the isoform population. Conclusion(s): Our data suggest that intronic variation of SOHLH2 is associated with spermatogenic failure. The genetic effect is likely caused by different haplotypes of rs6563386 and rs1328626, which may predispose to SO or TESE- depending on the specific allelic combination.
- Pesquisa de microdeleções AZF em homens inférteis na população portuguesaPublication . Pereira-Caetano, Iris; Silva, Júlia; Correia, Sónia; Pinto, Maria Graça; Rangel, Ricardo; Aguiar, Ana; Nunes, Joaquim; Calhaz, Carlos; Gonçalves, JoãoA infertilidade conjugal, definida como a incapacidade de conceção de um casal ao fim de um ano de relações sexuais desprotegidas, afeta 10 a 15% dos casais em idade reprodutiva, sendo que as causas masculinas constituem 30 a 40% das causas de infertilidade dos casais. Etiologicamente, a infertilidade masculina pode ter origem genética e não genética. De entre as causas genéticas mais frequentes destacam-se as alterações numéricas ou estruturais dos cromossomas, as mutações no gene CFTR e as microdeleções do cromossoma Y. No braço longo do cromossoma Y, em Yq11.2, localizam-se três regiões AZF (Azoospermia factor), AZFa, AZFb e AZFc, fundamentais para a fertilidade masculina uma vez que possuem múltiplos genes com expressão testicular implicados nas diferentes etapas da espermatogénese (1,2). As microdeleções do Y podem abranger uma ou mais destas regiões, e dependendo da região AZF delecionada ou ausente, a fertilidade pode ser mais ou menos afetada, observando-se diferentes padrões histológicos testiculares, que vão desde o síndrome de só-células-de-sertoli (deleção de AZFa), a paragem de maturação dos gâmetas durante a meiose (deleção AZFb) e a hipoespermatogénese (deleção de AZFc). Estas microdeleções representam a segunda causa genética mais frequente de falha espermatogénica em homens inférteis a seguir ao síndrome de klinefelter (cariotipo 47,XXY). O diagnóstico molecular das microdeleções AZF no cromossoma Y é um teste genético recomendado por rotina em homens inférteis que apresentem oligozoospermia grave (<5x106 espermatozoides/ml de sémen ejaculado) ou azoospermia secretora de causa desconhecida.