Since the patients with SCA were in Hardy-Weinberg equilibrium, the genotypes of the promoter region (-550 H/L, −221 X/Y) were grouped with those of exon 1 (A/O) and the correlation with MBL serum concentrations was used to classify the patients as having low, intermediate and normal MBL expression (Garred et al., 2003). Here, MBL2 is linked to autosomal dominant cerebellar ataxia.