|Number of repeats||Counts (alleles)||Percentage|
Overview of repeats
The normal length of repeats for CACNA1A gene is usually between 4 and 16 repeats (Zhuchenko et al., 1997), but a healthy individual carrying 18 repeats in the allele have been found as well (Riess, 1997). An affected individual being homozygous for an intermediate allele of 19 repeats has been described in Italian family (Mariotti et al., 2001). The pathogenic range starts from 21 repeats of CAG which is known to cause spinocerebellar ataxia type 6 (Riess, 1997).