Huntington's disease in Chile: epidemiological and genetic aspects

Introduction: Huntington ’s disease (HD) is a neurodegenerative, autosomal dominant disabling condition due to an expansion of the CAG trinucleotide in the HTT gene. Motor, psychiatric, and cognitive disorders characterize it. Chilean reports on HD in the era of molecular diagnosis were wanted. Methods: This is a retrospe ctive analysis of a prospective cohort of patients with HD seen at the Center for Movement Disorders (CETRAM) in Chile between 2013 and 2019. Sociodemographic, genotype, and neuropsychiatric features were investigated. Results: One hundred-three proband with HD were identified. The majority (63.1%) were born in the metropolitan region, followed by the VIII and V regions, with 8.73% and 7.76%, respectively. When pedigrees were analyzed, ninety unrelated families encompassing 1007 individuals were identified; among relatives, other 35 manifested HD, and 106 died of HD. Besides, five hundred seve nty-nine individuals were at genetic risk. The minimum estimated prevalence of HD in Chile in 2019 was 0.72 x 100,000 inhabitants. The mean CAG repeats (CAGR) of 47.2 ± 10.74 for the expanded allele and 17.93 ± 2.05 for the normal allele. The mean age of onset was 41.39 ± 13.47 years. Juvenile ca ses represented 7.8% of this cohort, and 4.9% had a late-onset. There was a negative correlation between the age of onset and the CAGR of the expanded allele (r = - 0.84 p
Source: Neuroepidemiology - Category: Epidemiology Source Type: research