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Abstract Introduction: Non-syndromic orofacial clefts have a complex etiology due to the contribution from both genetic and environmental risk factors, as well as the interaction between them. Among the more than 15 susceptibility loci for non-syndromic orofacial clefts with considerable statistical and biological support, the IRF6 is the most validated gene by the majority of studies. Nonetheless, in genetically heterogeneous populations such as Brazilian, the confirmation of association between non-syndromic orofacial clefts and IRF6 common variants is not a consolidated fact and unrecognized IRF6 variants are poorly investigated. Objective: The aim of this study was to investigate the association of IRF6 polymorphisms with non-syndromic orofacial clefts development in a population from northeast Brazil. Methods: Blood samples of 186 non-syndromic orofacial clefts patients and 182 controls from Rio Grande do Norte, Brazil, were obtained to analyze IRF6 polymorphisms (rs2235371, rs642961, rs2236907, rs861019, and rs1044516) by real-time polymerase chain reaction. Non-syndromic orofacial clefts patients were classified in cleft lip and palate, cleft palate only and cleft lip only groups. Results: The genotype and allele frequencies of single nucleotide polymorphism rs2235371 in IRF6 showed significant differences in patients with cleft palate when compared to the controls, whereas no association was shown between rs642961, rs2236907, rs861019, and rs1044516 and non-syndromic orofacial clefts. Conclusion: The association found between rs2235371 and isolated cleft palate should be interpreted with caution due to the low number of individuals investigated, and more studies with larger sample size are needed to confirm these association. In addition, there is a lack of association of the rs642961, rs2236907 and rs861019 polymorphisms with non-syndromic orofacial clefts susceptibility.
Resumo Introdução: As fendas orofaciais não sindrômicas possuem uma etiologia complexa devido à contribuição de fatores de risco genéticos e ambientais, assim como a interação entre eles. Dentre os mais de 15loci de susceptibilidade para as fendas orofaciais não sindrômicas com considerável suporte estatístico e biológico, o IRF6 é o gene mais validado pela maioria dos estudos. Apesar disso, em populações geneticamente heterogêneas como a brasileira, a confirmação da associação entre as fendas orofaciais não sindrômicas e as variantes mais comuns do IRF6 ainda não é um fato consolidado e outras variantes não tão conhecidas IRF6 são pouco investigadas. Objetivo: O objetivo deste estudo foi investigar a associação de variados polimorfismos do IRF6 com o desenvolvimento das fendas orofaciais não sindrômicas em uma população do nordeste do Brasil. Método: Amostras de sangue de 186 pacientes com fendas orofaciais não sindrômicas e 182 controles do estado do Rio Grande do Norte, Brasil, foram obtidas para analisar os polimorfismos do IRF6 (rs2235371, rs642961, rs2236907, rs861019 e rs1044516) por reação em cadeia da polimerase em tempo real. Os pacientes com fendas orofaciais não sindrômicas foram classificados em fenda labiopalatina, fenda palatina isolada e fenda labial isolada. Resultados: As frequências genotípica e alélica do polimorfismo de único nucleotídeo rs2235371 no IRF6 mostraram-se significativamente diferentes em pacientes com fenda palatina isolada quando comparadas às dos controles, enquanto que nenhuma associação foi encontrada entre rs642961, rs2236907, rs861019 e rs1044516 e risco para o desenvolvimento das fendas orofaciais não sindrômicas. Conclusão: A associação encontrada entre rs2235371 e fenda palatina isolada deve ser interpretada com cautela devido ao baixo número de indivíduos investigados, sendo necessários mais estudos com um tamanho amostral maior para confirmar essa associação. Além disso, não foram encontradas associações significativas entre os demais polimorfismos do IRF6 rs642961, rs2236907, rs861019 e rs1044516 e a susceptibilidade às fendas orofaciais não sindrômicas.
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Humanos , Labio Leporino/genética , Fisura del Paladar/genética , Factores Reguladores del Interferón/genética , Polimorfismo Genético , Brasil , Predisposición Genética a la Enfermedad , GenotipoRESUMEN
Orofacial clefts can transpire either, as part of complex malformation syndromes, or as an isolated entity, also called non-syndromic cleft. Cleft lip with or without cleft palate (CL/P), collectively termed oral clefts, are the second most commonly observed birth defects among newborns after congenital heart defects. We wanted to investigate the association between genetic polymorphism in Interferon Regulatory Factor 6 (IRF6) & non-syndromic cleft lip and palate (CL/P) cases in Central Indian population.METHODSIn this cross-sectional observational study, the sample comprised of Group 1: 66 individuals and 7 affected families with non-syndromic CL/P; and Group 2: 30 normal individuals and 10 normal families. 5 ml blood sample was collected from each individual following proper surgical protocol using disposable syringes, in blood tubes containing EDTA, with proper labelling and coding for further identification. DNA extraction was done by phenol chloroform extraction protocol and amplification was done using Polymerase Chain Reaction (PCR). Genotyping for the IRF6 polymorphism was completed by restriction digestion of PCR products, also called Restriction Fragment Length Polymorphism (RFLP).RESULTSThe correlative comparison between GG and GA polymorphism in IRF6 gene between affected cases and normal patients shows highly significant value. The comparison between GG & GA polymorphism shows that GG polymorphism is significantly higher in affected cases compared to Group 2. While GA polymorphism is significantly low or decreased in non-syndromic CL/P patients when compared to control group.CONCLUSIONSGG polymorphism is more frequently associated with non-syndromic CL/P as compared to GA polymorphism.
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Abstract Introduction Transcription factors are very diverse family of proteins involved in activating or repressing the transcription of a gene at a given time. Several studies using animal models demonstrated the role of transcription factor genes in craniofacial development. Objective We aimed to investigate the association of IRF6 intron-6 polymorphism in the non-syndromic cleft lip with or without palate in a South Indian population. Methods 173 unrelated nonsyndromic cleft lip with or without cleft palate patients and 176 controls without clefts patients were genotyped for IRF6 rs2235375 variant by allele-specific amplification using the KASPar single nucleotide polymorphism genotyping system. The association between interferon regulatory factor-6 gene intron-6 dbSNP208032210:g.G>C (rs2235375) single nucleotide polymorphism and non-syndromic cleft lip with or without palate risk was investigated by chi-square test. Results There were significant differences in genotype or allele frequencies of rs2235375 single nucleotide polymorphism between controls and cases with non-syndromic cleft lip with or without palate. IRF6 rs2235375 variant was significantly associated with increased risk of non-syndromic cleft lip with or without palate in co-dominant, dominant (OR: 1.19; 95% CI 1.03-2.51; p = 0.034) and allelic models (OR: 1.40; 95% CI 1.04-1.90; p = 0.028). When subset analysis was applied significantly increased risk was observed in cleft palate only group (OR dominant: 4.33; 95% CI 1.44-12.97; p = 0.005). Conclusion These results suggest that IRF6 rs2235375 SNP play a major role in the pathogenesis and risk of developing non-syndromic cleft lip with or without palate.
Resumo Introdução Fatores de transcrição constituem uma família de proteínas muito diversa envolvida na ativação ou repressão da transcrição de um gene, em um determinado momento. Vários estudos usando modelos animais demonstraram o papel dos genes do fator de transcrição no desenvolvimento craniofacial. Objetivo Nosso objetivo foi investigar a associação do polimorfismo IRF6 intron-6 na fenda labial não sindrômica com ou sem fenda palatina em uma população do sul da Índia. Método Um total de 173 pacientes com fenda labial não sindrômica com ou sem fenda palatina e 176 controles sem fendas foram genotipados para a variante IRF6 rs2235375 por amplificação alelo-específica utilizando o sistema KASPar de genotipagem de polimorfismo de nucleotídeo único. A associação entre o polimorfismo de nucleotídeo único Fator 6 Regulatório do Interferon (IRF6) intron-6 dbSNP208032210:g.G>C (rs2235375) e o risco de fenda labial não sindrômica com ou sem fenda palatina foi investigado pelo teste qui-quadrado. Resultados Houve diferenças significativas nas frequências de genótipos ou alelos do rs2235375 SNP entre controles e casos com fenda labial não sindrômica com ou sem fenda palatina. A variante IRF6 rs2235375 foi significativamente associada ao aumento do risco de fenda labial não sindrômica com ou sem fenda palatina em modelos codominantes, dominantes (OR: 1,19; IC 95%: 1,03-2,51; p = 0,034) e alélicos (OR: 1,40; IC 95%: 1,04-1,90; p = 0,028). Quando a análise do subgrupo foi realizada, um risco significativamente aumentado foi observado no grupo Fenda Palatina Isolada (OR dominante: 4,33; IC 95%: 1,44-12,97; p = 0,005). Conclusões Esses resultados sugerem que o polimorfismo de nucleotídeo único IRF6 rs2235375 desempenha um papel importante na patogênese e no risco de desenvolvimento de fenda labial não sindrômica com ou sem fenda palatina.
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Humanos , Masculino , Femenino , Labio Leporino/genética , Fisura del Paladar/genética , Polimorfismo de Nucleótido Simple/genética , Factores Reguladores del Interferón/genética , Estudios de Casos y Controles , Factores de Riesgo , Labio Leporino/etnología , Fisura del Paladar/etnología , Estudios de Asociación Genética , Técnicas de Genotipaje , Frecuencia de los Genes , IndiaRESUMEN
Abstract Non-syndromic cleft lip with or without palate (NSCL/P) is a common congenital malformation worldwide, with complex etiology. It has been proposed that interaction of genes and environmental factors play a role in the predisposition to this disease. Objectives: The aim of this study was to examine the association between AXIN2 (axis inhibition protein 2) rs7224837, BMP4 (bone morphogenetic protein 4) rs17563, and IRF6 (interferon regulatory factor 6) rs861019 and 2235371 polymorphisms and NSCL/P in an Iranian population. Material and Methods: This case-control study was carried out on 132 unrelated NSCL/P patients and 156 healthy subjects. The variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The findings suggest that BMP4 rs17563 polymorphism significantly decreased the risk of NSCL/P in codominant (OR=0.36, 95%CI=0.17-0.79, p=0.012, CT vs CC and OR=0.11, 95%CI=0.01-0.88, p = 0.019, TT vs CC), dominant (OR=0.30, 95%CI=0.15-0.62, p = 0.0007, CT+TT vs CC), recessive (OR=0.12, 95%CI=0.02-0.99, p = 0.023, TT vs CC+CT), overdominant (OR=0.39, 95%CI = 0.18-0.84, p=0.021, CT vs CC+TT), and allele (OR=0.28, 95%CI=0.15-0.55, p<0.0001, T vs C) inheritance models. Our findings did not support an association between AXIN2 rs7224837 and IRF6 rs861019 polymorphism and risk/protection of NSCL/P. The IRF6 2235371 variant was not polymorphic in our population. Conclusion: The results indicate that the BMP4 rs17563 variant is likely to confer a protective effect against the occurrence of NSCL/P in a sample of the southeast Iranian population.
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Humanos , Masculino , Femenino , Niño , Labio Leporino/genética , Fisura del Paladar/genética , Factores Reguladores del Interferón/genética , Proteína Morfogenética Ósea 4/genética , Proteína Axina/genética , Polimorfismo de Longitud del Fragmento de Restricción , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Frecuencia de los Genes , Genotipo , IránRESUMEN
Objective:To study the association between the rs2013162 and rs2235375 polymorphisms in IRF6 and risk of NSCL/P in west Chinese population. Methods: The study group consisted of 332 NSCL/P patients, their parents (289 mothers, 243 fathers and 206 complete families), and 174 controls. PCR-RFLP method was used to identify genotypes and both case-parent and case-control designs were carried out on samples from west China. Results: There were significant differences in the frequency distributions of both genotypes and alleles when cases were compared with control infants at the rs2235375(P<0.01, P<0.01 respectively). We found strong evidence of over-transmission of the G allele at rs2235375 in cleft case-parent trios(P<0.01). Five specific haplotypes showed significant over-and under-transmission. Conclusion: These results suggest IRF6 variants play a role in NSCL/P in west Chinese populations.
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Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common craniofacial birth defect that is the result of a mixture of genetic and environmental factors. While studies have identified a number of different candidate genes and loci for the etiology of CL/P, the results have not been consistent among different ethnic groups. To study the genetic association of the candidate genes in Korean patients affected by CL/P, we genotyped 97 nonsyndromic CL/P patients and 100 control individuals using single nucleotide polymorphic markers at the MTHFR, TGFA, and IRF6 genes. We report that the T3827C marker at TGFA showed significant association with nonsyndromic CL/P, but all the other markers tested were not significantly associated with nonsyndromic CL/P in Korean patients.