Sib-pair linkage analysis of longitudinal changes in lipoprotein risk factors and lipase genes in women twins

Based on longitudinal twin data in women, we have previously demonstrated a genetic influence on changes in lipoprotein risk factors, blood pressure m easurements, and body mass index over a decade. The present study examined the linkage between changes in lipoprotein variables and candidate genes en coding the hormone-sensitive lipase (HSL), hepatic lipase (HL), and lipopro tein lipase (LPL), The sample consisted of 126 dizygotic (DZ) pairs of wome n twins who participated in the two examinations of the Kaiser Permanente W omen Twins Study, performed a decade apart. Using quantitative sib-pair lin kage analysis, a linkage was demonstrated between the locus for hormone-sen sitive lipase and age-adjusted changes in plasma triglyceride (P = 0,015), which became more significant after adjustment for environmental factors an d the exam-1 level (P = 0,005), There was also evidence suggesting linkage between the locus for hepatic lipase and changes in triglyceride (P = 0,023 ), but no linkage was detected for lipoprotein lipase and changes of lipid levels with time.jlr These findings suggest that variation at these candida te gene loci may underlie a portion of the intraindividual variations in th ese corollary heart disease (CHD) risk factors, and that studies to identif y the functional variants could provide new insights into genetic susceptib ility to cardiovascular disease.