Investigation of trinucleotides expansion level in Huntington disease with triplet repeats PCR

Huntington disease is a debilitating genetic neurodegenerative disease of the central nervous system manifesting by various movement disorders, neuropsychiatric symptoms and mood abnormalities. Huntington disease is categorized by trinucleotide repeat expansion disorder and characterized by increase in number of CAG-triplet in HTT gene. Determination of expansion of CAG-repeats is obligatory for the diagnosis of Huntington disease. Besides that, measuring of CAG-repeats quantity can help to predict future course of the disease. This article is dedicated to the study of the quantity of CAG-repeats in HTT gene in patients with the Huntington disease and in the control group without neurological symptoms. Triplet repeat PCR technique and capillary electrophoresis were used for the detection of CAG-repeats. Validation of system helped to determine basic analytic parameters of test and showed its high reproducibility and precision. Approbation of test system in patients with the Huntington disease showed that in all tested samples had moderate or significant expansion of CAG-repeats. The amount of CAG-triplets in the control group did not exceed limits of normal. Triplet repeats PCR allows determining the quantity of CAG-triplets with high precision and reproducibility, to decrease the time of the test conduction and to simplify the whole procedure.

Болезнь Гентингтона, CAG-повторы, экспансия, ПЦР тройных повторов, Huntington disease, CAG-repeats, expansion, triplet repeats PCR

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