Leukocyte beta-glucosidase in a child with Gaucher's disease and his kinship.

Beta-glucosidase was determined in leukocyte homogenates of a male child with Gaucher's disease and members of his family. An important difference in enzyme activity was found in the heterozygous gene carriers; in one obligate heterozygote, the mother, a high residual enzyme capacity was detected. Various methods of enzyme determination using various substrates are recommended for the detection of the gene carrier condition.