Phenotypic and genotypic features of children with familial hypercholesterolemia

Dyslipidemia is a metabolic disorder in which the ratio of lipid particles in the blood changes. It is often associated with other conditions and diseases during childhood. Lipid metabolism disorders in children can be divided into two categories: primary, which are inherited from parents or occur de novo, and secondary, which occur during life. Familial hypercholesterolemia is the most common type of primary disorder, characterized by an increase in blood lipoprotein levels. However, the lipid composition in children with established familial hypercholesterolemia can vary. One factor that may contribute to higher lipid levels in these children is the presence of mutations in the apolipoprotein E gene. Purpose of the study was to investigate the phenotypic and genotypic features of children with familial hypercholesterolemia in order to better understand this condition. Materials and methods. Children with a clinical diagnosis of familial hypercholesterolemia underwent DNA sequencing to identify mutations in genes related to LDLR, APOB, LDLRAP1, and APOE genes. Results. Children with familial hypercholesterolemia most often carry the polymorphism c.388T>C in the ApoE gene (g.45411941T>C, p.Cys130Arg, rs429358). Also, 24.1% of children were found to be isolated carriers of various ApoE haplotypes, which are risk factors for dyslipidemia. In children with a pathogenic mutation characteristic of familial hypercholesterolemia and carriage of polymorphisms in the ApoE gene, the LDL level was statistically higher compared to non-carriers. Conclusion. Carriage of various polymorphisms in the ApoE gene in children with familial hypercholesterolemia may lead to an increase in the already elevated levels of LDL and total cholesterol.