Genome-wide linkage scan for loci influencing plasma triglycerides

BackgroundPlasma triglyceride concentration is known to be a significant risk factor for cardiovascular disease (CVD). Previous studies have found that the level of triglycerides is strongly influenced by genetic factors.MethodsTo identify quantitative trait loci influencing triglycerides, we conducted a genome-wide linkage scan on data from 485 Australian adult dizygotic twin pairs. Prior to linkage analysis, triglyceride values were adjusted for the effects of covariates including age, sex, time since last meal, time of blood collection (CT) and time to plasma separation.ResultsThe heritability estimate for ln(triglyceride) adjusted for all above fixed effects was 0.49. The highest multipoint LOD score observed was 2.94 (genome-wide p = 0.049) on chromosome 7 (at 65 cM). This 7p region contains several candidate genes. Two other regions with suggestive multipoint LOD scores were also identified on chromosome 4 (LOD score = 2.26 at 62 cM) and chromosome X (LOD score = 2.01 at 81 cM).ConclusionsThe linkage peaks found represent newly identified regions for more detailed study, in particular the significant linkage observed on chromosome 7p13.