Please visit our Spinocerebellar Ataxia General Information page for information about this rapidly changing area of neurology.The primary citations on the identification of this gene can be found in: Pulst et al. (1996) Nature Genetics 14: 269-276; Sanpei et al. (1996) Nature Genetics 14:277-284. Current OMIM information on SCA 2 can be found at: #183090In the figure below, a normal, heterozygous SCA 2 genotype of 22 & 23 CAG allele repeats is shown in lane 1, the most common homozygous SCA 2 genotype of 22 CAG allele repeats is shown in lane 2, while SCA 2 alleles of 22 & 39 CAG repeats found in an individual affected with SCA 2 are shown in lane 3. The normal SCA 2 22 CAG repeat allele is found on about 92% of chromosomes; the 23 CAG repeat allele is found on most other chromosomes. Normal SCA 2 CAG repeats has been found to range between 17 and 29 repeats. Individuals affected with SCA 2 have one SCA 2 CAG repeat allele of between 36 and 52 CAG repeats. The most common SCA 2 affected allele has 37 CAG repeats. DNA size standards are depicted in the lanes labelled GATC.