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Spinocerebellar ataxias (SCA) form a group of clinically and genetically heterogeneous disorders with the main presenting feature of disturbed motor coordination and balance. They are subdivided into autosomal dominant (ADSCA), autosomal recessive (ARSCA), X-linked and mitochondrial ataxias. Our study is focused on the ARSCA which present with an earlier age of onset (<20 years old). Genetic studies thus far revealed 9 ARSCA genes and 7 additional ARSCA gene loci. Our aim is to identify the disease causing mutation in the group of 12 already ascertained Cypriot ARSCA families. These families were previously excluded from GAA repeat expansion in intron 1 of the FXN gene and a novel Cypriot SETX mutation. The diagnosis of ataxia with vitamine E deficiency was excluded biochemically. Our current investigation involves analysis of 9 of the known ARSCA genes/loci (APTX, SETX, POLG, TDP1, SACS, SYNE1, C10orf2, SCAR3, SCAR7). We perform genotype, linkage and haplotype analyses at these loci. Genotype analysis is performed for all available family members at three marker loci per gene/locus. The samples are analyzed by PCR followed by fragment analysis. Linkage analysis is performed using the MLINK program and for the haplotype analysis the Cyrillic 2.1 pedigree drawing program and database is used. For the families linked to a known ARSCA gene, mutation identification in the corresponding gene will be initiated through sequencing of the proband’s sample. Thus far four families were excluded from all the above loci thus indicating the existence of novel ARSCA loci/genes in the Cypriot population. The remaining families had some indication for linkage to some of the above loci and are currently under further investigation for confirmation or exclusion of linkage.