Análise da influência do polimorfismo rs1801133 (677c>t) no gene mthfr em fissuras labiais com ou sem fissura palatina não sindrômicas: estudo de base familiar e populacional pareado por ancestralidade no Brasil

• Ano de defesa: 2014
• Autor(a) principal: Aguiar, Pamella Kelly Farias de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraí­ba; Brasil; Biologia Celular e Molecular; Programa de Pós-Graduação em Biologia Celular e Molecular; UFPB
• Palavras-chave em Português: Fissura Labial e Labiopalatina não sindrômicas; Polimorfismo do Gene MTHFR; Estudo Caso-Controle; Teste de Desequilíbrio de Transmissão - TDT; Monsyndromic cleft lip palate; MTHFR polymorphism; Case-Control Studies; Transmission disequilibrium test; CIENCIAS BIOLOGICAS::BIOLOGIA GERAL
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/tede/3658

The MTHFR 677C>T variant (rs1801133) has been analysed as a putative genetic risk factor for oral clefts within various populations worldwide. To test the role of the MTHFR 677C>T variant in nonsyndromic cleft lip with or without cleft palate (NSCL/P) predisposition in the Brazilian population, we conducted a study combining a family-based association test (transmission disequilibrium test-TDT) and a structured association analysis (case-control study) based on the individual ancestry proportions. The rs1801133 polimorphism was genotyped in 197 trios with NSCL/P, 318 isolated samples of NSCL/P and 598 healthy controls using the TaqMan 5′- exonuclease allelic discrimination assay. Genomic ancestry was characterized by a set of 40 biallelic short insertion/deletion markers. TDT revealed a strong association of rs1801133 polymorphism with case-parent trios of NSCL/P (p=0.002) and non-syndromic cleft lip and palate (NSCLP, p=0.001), but not with non-syndromic cleft lip (NSCL). Analyses of parent-oforigin effects demonstrated modest excess transmission of the risk allele from mothers of NSCLP (OR: 1.47, 95% CI: 1.10-2.14, p=0.04). The structured case-control analysis supported these findings, revealing that the risk T allele was significantly more frequent in NSCL/P group (OR: 1.37, 95% CI: 1.12-1.69, p=0.002) and NSCLP (OR: 1.41, 95% CI: 1.12-1.79, p=0.01) than the control group. Our findings provide evidence for the involvement of rs1801133 in the development of NSCL/P in the Brazilian population, and reinforce the importance of genetic screening in populations at risk in order to optimize the implementation of preventive strategies.