Serum cholesterol levels in patients with familial hypercholesterolemia confirmed by tissue culture.

Sixty-two subjects from 23 families were evaluated by serum lipid analyses and tissue culture biochemistry in skin fibroblasts. In 53 cases from 19 families with proven familial hypercholesterolemia (FHC), fibroblast cultures were successful. In 45 of these cases (85%) the clinical diagnosis of hyper- or normocholesterolemia was in accordance with the tissue culture findings. Four patients 2-38 years old, had hypercholesterolemia but normal tissue culture results. Four patients, 18-44 years old, had normal serum cholesterol levels for their age and sex, but were heterozygotes according to tissue culture results. In the remaining four families only the propositus had hypercholesterolemia. All members of the families including the propositus had normal tissue culture determinations indicating that not all cases of idiopathic hypercholesterolemia are due to the Goldstein-Brown mechanism of defective LDL receptor function.