The relationship between demographical, clinical properties and their mutation analysis results between children and adolescents with the diagnoses of primary familial hyperlipidemia

Objective: In this study; to investigate the demographical, clinical properties and the treatments used, to examine genetic mutations and to obtain a genotype-phenotype relation in patients with the diagnoses of primary familial hyperlipidemia were intended. Material and Method: The demographical features, personal and familial characteristics, clinical findings and laboratory results were reviewed in eighty children and adolescents who were followed with the diagnoses of primary familial hyperlipidemia during the study period of April 2014 - October 2015 in Çukurova University Pediatric Metabolism and Nutrition Department. Also, the genetic mutations responsible for the disease were investigated. Mutation analysis were performed for the genes LDLR, LDLRAP1, Apo B, PCSK9, ABCG5, ABCG8, LPL, Apo C-II, Apo A-V, RP1, LIP1. Results: Forty-two of all 80 patients (% 52,5) were females and 38 of them (% 47,5) were males. From 30 of the patients with hypertriglyceridemia, mostly LPL gene and RP1, Apo c-II and Apo A-V gene mutations were detected. However, from 50 of the patients with hypercholesterolemia mostly had a mutation in LDLR and LDLRAP1 genes. With this study, 5 new mutations in LPL gene, 1 new mutation in Apo A-V gene and 4 new mutations in LDLR gene were defined. In patients with familial hypertriglyceridemia the mutations of 557G>A and c.953A>G in LPL gene were found to be compound heterozygous mostly. LDLR gene is found to be mostly responsible gene in the familial hypercholesterolemia group, which is consistent with the literature. The most common mutation was c.406C>T which is defined in LDLRAP1 gene. Conclusion: Primary familial hyperlipidemias are metabolical disorders which cause different clinical conditions based on the differences between plasma lipid levels. Detection of random findings like lipemic serum, abdominal pain, hepatosplenomegaly are detected as earlier symptoms in patients with familial hypertriglyceridemia. It is crucial to diagnose familial hypercholesterolemiain earlier childhood period to decrease the cardiovascular effects and to increase the survival rate. Different genetic mutations might have variable influences on the clinical course of the disease. This study is the most comprehensive study examining a large number of genes in our country among children and adolescents who have primary familial hyperlipidemia. Key Words: Familial hyperlipidemia, LDLR, LDLRAP1, LPL.