RESUMO
OBJECTIVES/HYPOTHESIS: Orofacial clefts are the most common craniofacial birth defects in humans, with the majority of orofacial clefts occurring as nonsyndromic cleft lip with or without cleft palate (NSCLP). We previously demonstrated associations between single-nucleotide polymorphisms (SNPs) in the IRF6 gene and NSCLP in the Honduran population. Here we investigated other candidate genes and chromosomal regions associated with NSCLP identified from genome-wide association studies (GWAS), including MAFB, ABCA4, 8q24, 9q22, 10q25, and 17q22 in two independent Hispanic populations. STUDY DESIGN: Case-control and family-based association testing. METHODS: Honduran families with two or more members with NSCLP (multiplex) were identified. DNA was collected from affected and unaffected family members (488) and 99 gender-matched controls. NSCLP Colombian families were identified; DNA was collected from 26 proband-parent trios. All participants were genotyped for 17 SNPs in six chromosomal regions. Case-control association and family-based association testing (FBAT) analyses were conducted. RESULTS: Seven SNPs demonstrated association in at least one model in the Honduran population. In the Colombian families, five SNPs demonstrated significance in FBAT when patients with isolated cleft palate (CP) were included; four overlapped with SNPs demonstrating significance in the Honduran population, two with the same allele. One SNP retained significance with CP excluded. CONCLUSIONS: This study supports the previous GWAS findings and is the first to suggest a role for FOXE1, ABCA4, and MAFB in orofacial clefting in two separate Hispanic populations.
Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Fenda Labial/genética , Fissura Palatina/genética , Fatores de Transcrição Forkhead/genética , Predisposição Genética para Doença/epidemiologia , Fator de Transcrição MafB/genética , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , Fenda Labial/etnologia , Fenda Labial/cirurgia , Fissura Palatina/etnologia , Fissura Palatina/cirurgia , Colômbia/etnologia , Intervalos de Confiança , Feminino , Estudos de Associação Genética , Estudo de Associação Genômica Ampla , Genótipo , Hispânico ou Latino/genética , Honduras/etnologia , Humanos , Incidência , Fatores Reguladores de Interferon/genética , Masculino , Razão de Chances , Linhagem , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: The etiology of mild hyperglycemia without ketoacidosis in young children is often unknown. Maturity onset diabetes of youth (MODY) is a form of diabetes mellitus (DM) characterized by fasting hyperglycemia without evidence for autoimmune destruction of beta-cells. METHODS: We genetically analyzed four families of young children with fasting hyperglycemia with family histories of diabetes for mutations in the genes for hepatocyte nuclear factor 4 alpha (HNF4alpha), glucokinase (GCK), and hepatocyte nuclear factor 1 alpha (HNF1alpha), the genes responsible for MODY1, MODY2, and MODY3, respectively. RESULTS: We identified mutations in GCK (Gly258Asp, Arg303Trp, and Arg191Gln) in three of the four families. Molecular genetic characterization in these children clarified the etiology and prognosis of the hyperglycemia and allowed discontinuation of insulin therapy in one family. CONCLUSIONS: We conclude that molecular evaluation for MODY in children with mild fasting hyperglycemia without ketosis with family histories of diabetes can provide important prognostic information to guide therapy and exclude preclinical type 1 diabetes mellitus.