Beta-mannosidosis: prenatal biochemical and morphological characteristics.

Caprine beta-mannosidosis, an autosomal recessive disorder of glycoprotein catabolism, as yet undetected in man, was expressed in a 96/150 day gestation goat fetus. Deficiency of plasma, kidney, brain, liver and skin fibroblast acidic beta-mannosidase activity was associated with the accumulation of tissue oligosaccharides. Characteristic lucent cytoplasmic lysosomal storage vacuoles were present in the brain, thyroid, kidney and other tissues. Axonal spheroids were present in the central nervous system. The biochemical and morphological prenatal expressions of beta-mannosidosis which were documented by this investigation may facilitate the identification of the disease in man.