Lekárska genetika a diagnostika 2/2024

Friedreich’s ataxia − population study in SR, possibilities of diagnosis and treatment

Friedreich’s ataxia (FRDA, MIM 229300) is a rare, inherited, autosomal recessive neurodegenerative disorder. In the most of cases we found the expansion of trinucleotide repeats (GAA) in the 1st intron of the FXN gene. The frequency of the disease in the Caucasoid race varies significantly between populations and ethnic groups (from 1:20,000 to 1:1,000,000). An estimation of the number of FRDA patients can be also made by an approximation based on the frequency of disease carriers. Our study is focused on the epidemiology of FRDA in the Slovak population and it was carried out by examining of a control group of individuals (1134 alleles). We found that the disease carrier frequency is 1:105. Based on these obtained data, the probability of having a newborn with FRDA in the Slovak population is 1:44 100. Considering the reduced fitness, shortened survival of FRDA patients and the demographic situation in Slovakia, we can reasonably estimate the number of living patients suffered with FRDA in Slovakia to 50-60 persons.

Keywords: Friedreich’s ataxia, FXN gene, carrier frequency, GAA expansion