Prenatal diagnosis of familial hypercholesterolemia caused by the "Lebanese" mutation at the low density lipoprotein receptor locus.

Here, we report the prenatal diagnosis of familial hypercholesterolemia in a Christian-Arab family that carries the "Lebanese" mutation, a single base substitution that creates a HinfI restriction site, at the low density lipoprotein (LDL) receptor locus. Polymerase chain reaction amplification and restriction analysis were performed on genomic DNA extracted from a chorionic villus sample. In conjunction with karyotype analysis, the fetus was identified as a heterozygous female. Analysis of LDL receptor restriction fragment length polymorphisms confirmed the presence of a male parent marker and revealed that the fetus inherited the mutant gene from its mother. This technique offers a simple and rapid diagnostic tool that can be carried out at an early stage of gestation. It is recommended for families and population groups with molecularly defined LDL receptor mutations.