Investigation of genetic variants in interferon regulatory factor 6 (IRF6) and the susceptibility to nonsyndromic cleft lip with or without cleft palate in the Brazilian population

• Grant number: 22/04221-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2022
• End date: August 31, 2023
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Ricardo Della Coletta
• Grantee: Letícia Pratali Dolce
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The orofacial cleft is the most common malformation in the face, with a prevalence between 0.36 and 1.54 per 1,000 live births in the Brazilian population. With a multifactorial etiology, nonsyndromic orofacial clefts are caused by interactions between environmental factors, such as smoking and medications, and genetic factors, with one of the most studied genes being the interferon regulatory factor 6 (IRF6). Previous studies with variants in or near IRF6 revealed highly variable results, with effects of risk, protection or even no effect, depending mainly on the ethnicity of the population. Due to the strong miscegenation, studies with the Brazilian population are conflicting and it is not possible yet to conclude about the participation of IRF6 in the etiology of the nonsyndromic orofacial clefts in the Brazilian population. In this study, we sought to identify the contribution of polymorphic variants in IRF6 to the occurrence of nonsyndromic cleft lip with or without cleft palate (NSCL±P) in the Brazilian population. The Tag-SNP strategy was used for the selection of single nucleotide polymorphisms (SNP) representative of the 6 haplotype blocks that involve IRF6 sequence and its upstream and downstream regions. The SNPs rs2073485, rs2235375, rs7552506, rs599021, rs642961, and rs2235371 will be genotyped using allelic discrimination fluorescent probes (Taqman® SNP Genotyping Assays) in a case-control study containing 801 samples from patients with NSCL±P and 881 healthy controls. Statistical analyses will be performed taking into account the proportion of genomic ancestry of each of the samples. It is expected with this project to contribute to the characterization of the influence of genetic variants in IRF6 on NSCL±P etiology in the Brazilian population. (AU)