Variantes no gene GLA e o perfil enzimático da alfagalactosidase a em pacientes com suspeita de Doença de Fabry

• Ano de defesa: 2019
• Autor(a) principal: Teixeira, Patricia Varela Lima [UNIFESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Fabry's Disease; Gene GLA; Alpha Galactosid A; Mutants; Doença De Fabry; Alfa Galactosidade A; Mutantes
• Link de acesso: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=7635824; https://repositorio.unifesp.br/handle/11600/59598

Objective: To analyze a database with molecular and biochemical results of patients with suspected Fabry disease. From these results, to evaluate the pathogenicity of the variants, as well as to carry out the in vitro characterization of novel mutations, and finally to trace the enzymatic profile of the genotypes in order to evaluate the impact of these variants on the enzyme. Methods: Bioinformatics tools were used to analyze the variants found in the GLA gene of patients with Fabry disease suspected. Patients were divided according to the genotype they carried in order to trace the enzymatic profile and correlation with the pathogenicity. For in vitrocharacterization, experiments were conducted on HeLa cells transfected with wild-type GLA or with mutants plasmids, finally, gene expression as well as the enzymatic activity of α-Gal A were evaluated. Results: 215 men and 48 women presented 103 variants in GLA exons; 57 variants were previously described as pathogenic, eleven described as unknown effect and the other 35 are family-specific mutations. The other patients presented variants in non-coding regions or had no alterations inGLA. In vitro analysis confirmed pathogenicity in mutations classified as pathogenic and possibly pathogenic; in the new mutations classified as with unknown effect, pathogenicity was confirmed in three mutations, the other four did not cause DF. The enzymatic profile revealed a possible non-pathogenicity of variants of unknown effect, as well as variants found in non-coding regions. Finally, the study of haplotypes formed by variants in non-coding regions revealed a high frequency in the control population, similar to that found in patients. Conclusion: The DBS enzymatic activity was markedly reduced in patients with mutations described as pathogenic, as well as in novel variants classified as pathogenic or possibly pathogenic (with in vitro confirmation) when compared with individuals presenting VUS, variants in non-coding regions or without variants, indicating non-pathogenic potential of these latter genotypes.