genotype-phenotype correlationin in Iranian patients with Kennedy disease

Kennedy (SBMA) is a X-linked recessive rare neurodegenerative disorder which is associated with an unstable expansion of CAG trinucleotide repeat in the first exon of the Androgen receptor on chromosome X and only occur in male. Kennedy cause sit expansion CAG repeat in the nuclear and transcription disorder of target gene. Also three nucleotide expansion CAG in AR causes disruption of molecular chaperon s function and mitochondrial toxicity. it in turn affects apoptosis and degeneration motorneurons. The main clinical manifestations are muscular weakness, tremor, bulbar signs (dysphonia, dysphagia, …), infertility and gynecomastia Aim of this study was to fine out the most available method to determine genotype correlation expansion repeats and patients phenotypes 50 patient with a clinical diagnosis of kennedy from un related families and were investigated for the CAG trinucleotide repeat expansion PCR-Sequencing were used to determine the CAG expansion.In 38 of patients were found expansion in normal range so it could be because of un clear clinical diagnosis. By using PCR-Sequencing 12 patients were found in long range expansion. In kennedy patients there was an inverse correlation between the size and age of onset of diseases.

Keywords:

Kennedy expansion , CAG reaped , Androgen receptor , investigation genotype-phenotype