rs1801133C>T polymorphism in MTHFR is a risk factor for nonsyndromic cleft lip with or without cleft palate in the Brazilian population.

BACKGROUND: The MTHFR rs1801131A>C and rs1801133C>T variants have been analyzed as putative genetic risk factors for oral clefts within various populations worldwide. METHODS: To test the role of these polymorphisms in nonsyndromic cleft lip with or without cleft palate (NSCL/P) in the Brazilian population, we conducted a study combining a Family-Based Association Test (transmission disequilibrium test) and a structured association analysis (case-control study) based on the individual ancestry proportions. The rs1801131 and rs1801133 were initially analyzed in 197 case-parent trios by transmission disequilibrium test, and polymorphisms showing significant association with NSCL/P were subsequently studied in independent sample composed of 318 isolated samples of NSCL/P and 598 healthy controls in a case-control approach. Genomic ancestry was characterized by a set of 40 biallelic short insertion/deletion markers. RESULTS: A strong overtransmission of the T allele of rs1801133 was observed in case-parent trios of NSCL/P (p = 0.002), but no preferential parent-of-origin transmission was detected. No association of rs1801131 polymorphism with NSCL/P was observed. The structured case-control analysis supported that the T allele was significantly more frequent in the NSCL/P group (odds ratio: 1.37; 95% CI: 1.12-1.69; p = 0.002) than in the control group. Both polymorphisms were in linkage disequilibrium (D' = 0.94 and r(2) = 0.79), and haplotype-transmission disequilibrium test for allelic combination of rs1801131 and rs1801133 showed a significant overtransmission of haplotype A-T to the affected NSCL/P offspring (p = 0.001). CONCLUSION: Our findings provide evidences for the involvement of rs1801133 in the development of NSCL/P in the Brazilian population.

Prevalência de doenças bucais em crianças portadoras de fissuras labiopalatinas / Prevalence of oral diseases in children with cleft lip and palate

Foram examinadas 45 crianças com idade compreendida entre dois e 12 anos, 28 do sexo masculino e 17 do feminino, e que estavam inscritas no Núcleo de Reabilitação de Fissurados do Hospital Universitário - UFPB, e buscavam o atendimento médico ou fonoaudiológico, devidamente autorizadas por um responsável (mãe ou pai), através da assinatura do consentimento livre e esclarecido. As doenças bucais mais prevalentes encontradas nesse grupo de crianças fissuradas foram: maloclusões (86 por cento), cáries (75 por cento), anomalias dentárias (53 por cento), doenças periodontais (42 por cento) e traumatismos dentários (11 por cento). Os autores concluíram que existe a necessidade de uma assistência odontológica constante em um programa para fissurados, para que seja mantida a saúde bucal desses pacientes e também sejam minimizadas as deformações faciais decorrentes dessa malformação