Five skin fibroblast lines from patients with G(M1)-gangliosidosis (2 cases; R201C/R201C and I51T/I51T), Morquio B disease (2 cases; W273L/W273L and Y83H/R482C), and galactosialidosis (1 case; Y395C/S90L) were used as enzyme sources.
A cell line stably expressing a chimaeric gene with a mutant PPCA cDNA containing an A1184-->G (Y395C) mutation, commonly detected in Japanese severe early-infantile type of galactosialidosis patients, showed an endoplasmic reticulum (ER)-like reticular fluorescence pattern.
The patients in a Japanese family with the severe early-infantile form of galactosialidosis were revealed to be homozygous for the A1184-G transition in the PPCA gene in both alleles, which leads to the Y395C substitution.