Huntington's disease (HD) is an autosomal dominant, progressive neuron-degenerative disorder that presents at an advanced age with chorea, cognitive deterioration and psychiatric symptoms. HD is caused by expansion (>36) of CAG trinucleotide repeats in exon 1 of the IT15 gene. In this paper we present the results of HD gene analysis in 10 families from the Republic of Macedonia. The conventional analysis included polymerase chain reaction (PCR) amplification of exon 1 of the IT15 gene, denaturing poly­acrylamide gel electrophoresis (PAGE) of the resulting fragments, transfer to a nylon membrane, hybridization with a digoxigenin labeled internal probe and visualization by autoradiography. An automated fluorescent PCR method was also developed that allows fast, easy and reliable routine HD testing in our laboratory. Alleles with expanded trinucleotide repeats were detected in six of the seven patients, which ranged from 42 to 46 repeats and in two asymptomatic individual (46 repeats). In one patient and in one asymptomatic individual two normal alleles were detected (range 15 to 26 repeats) which excluded the presence of HD disease.

      Key words: Huntington's disease (HD), CAG tri­nucleotide repeats, IT15 gene.