RESEARCH ARTICLE Molecular epidemiology o i

GM1 gangliosidosis, a lysosomal storage disease that af-fects the brain and multiple systemic organs, is caused by an autosomal recessively inherited deficiency in acid β-galactosidase, which is encoded by the GLB1 gene [1]. GM1 gangliosidosis in Shiba Inu dogs was first reported in 2000 [2]. The causative mutation has been identified as a deletion of the cytosine in exon 15 at nucleotide position 1647 in the putative coding region (c.1647delC) of the canine GLB1 gene [3], thereby enabling molecular diagnosis and/or genotyping with polymerase chain reac-tion (PCR)-based DNA tests [4,5]. Affected dogs mani-fest neurological signs of progressive motor dysfunction from 5–6 months of age and die at 12–18 months after a clearly defined clinical course [6,7], which is associate