CpG hotspot mutations at the LDL receptor locus are a frequent cause of familial hypercholesterolemia among South African Indians

Abstract

Mutation analysis of genomic DNA samples obtained from seven unrelated South African Indians with familial hypercholesterolaemia (FH) revealed two novel and two recurrent missense mutations in the low density lipoprotein receptor (LDLR) gene. The novel mutations are transversions of C to G and A to T at nucleotide positions 1215 (N384K) and 2356 (S765C), respectively. The known mutations were detected in CpG dinucleotides at bases 661 and 682, respectively, in the mutation-rich exon 4 of the LDLR gene. Mutation D200Y was found in a single FH family, while mutation E207K was detected in two apparently unrelated Indian families on a new mutual haplotype. Analysis of published mutations including our new data has shown that more than 50% of the different LDLR gene mutations identified to date in South African Indians occur at CpG hotspots.