Fine mapping and association studies of a high-density lipoprotein cholesterol linkage region on chromosome 16 in French-Canadian subjects

Eur J Hum Genet. 2010 Mar;18(3):342-7. doi: 10.1038/ejhg.2009.157. Epub 2009 Oct 21.

Abstract

Low levels of high-density lipoprotein cholesterol (HDL-C) are an independent risk factor for cardiovascular disease. To identify novel genetic variants that contribute to HDL-C, we performed genome-wide scans and quantitative association studies in two study samples: a Quebec-wide study consisting of 11 multigenerational families and a study of 61 families from the Saguenay-Lac St-Jean (SLSJ) region of Quebec. The heritability of HDL-C in these study samples was 0.73 and 0.49, respectively. Variance components linkage methods identified a LOD score of 2.61 at 98 cM near the marker D16S515 in Quebec-wide families and an LOD score of 2.96 at 86 cM near the marker D16S2624 in SLSJ families. In the Quebec-wide sample, four families showed segregation over a 25.5-cM (18 Mb) region, which was further reduced to 6.6 Mb with additional markers. The coding regions of all genes within this region were sequenced. A missense variant in CHST6 segregated in four families and, with additional families, we observed a P value of 0.015 for this variant. However, an association study of this single-nucleotide polymorphism (SNP) in unrelated Quebec-wide samples was not significant. We also identified an SNP (rs11646677) in the same region, which was significantly associated with a low HDL-C (P=0.016) in the SLSJ study sample. In addition, RT-PCR results from cultured cells showed a significant difference in the expression of CHST6 and KIAA1576, another gene in the region. Our data constitute additional evidence for a locus on chromosome 16q23-24 that affects HDL-C levels in two independent French-Canadian studies.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Canada
  • Cholesterol, HDL / genetics*
  • Chromosomes, Human, Pair 16 / genetics*
  • France
  • Gene Expression Regulation
  • Genetic Linkage*
  • Genetic Predisposition to Disease*
  • Genome, Human
  • Humans
  • Lod Score
  • Physical Chromosome Mapping*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Sequence Analysis, DNA

Substances

  • Cholesterol, HDL
  • RNA, Messenger