Elevated plasma lipoprotein levels play a crucial role in the development o
f coronary artery disease. Genetic Factors strongly influence the levels of
plasma lipoproteins, but the genes and sequence variations contributing to
the most common Forms of dyslipidemias are not known. We used GeneChip pro
be arrays to resequence the coding regions of 10 key genes of lipid metabol
ism. The sequences of these genes were analyzed in 80 dyslipidemic individu
als. Fourteen nonsynonymous and twenty-two synonymous single nucleotide cha
nges were identified that could be confirmed by conventional sequencing. Se
ven of the fourteen nonsynonymous sequence variants were polymorphisms with
allele frequency >1% in the general population. The remaining seven were n
ot found in normolipidemic controls (25 Caucasians and 25 African-Americans
). The relationship between nonsynonymous sequence variations and various d
yslipidemias was explored in association and family studies. No evidence wa
s Found For coding sequence variations in any of the 10 genes contributing
to dyslipidemia. Only a single sequence variation, a missense mutation in t
he low density lipoprotein receptor gene, co-segregated with hyperlipidemia
in the proband's family. This study illustrates some of the difficulties a
ssociated with identifying sequence variations contributing to complex trai
ts.