Beta-galactosidase deficiency: Studies of two patients with prolonged survival

Two adults with β‐galactosidase deficiency were studied. Differences in a number of β‐galactosidase parameters (pH optima, heat denaturation, NaCl kinetics) were noted between the patients. Differences were also noted in β‐galactosidase electrophoretic mobilities and urinary oligosaccharides; however, there was no complementation in cell fusion studies. It is suggested that these two patients have different primary mutations at the β‐galactosidase locus which are probably structural in nature.