A genome-wide linkage scan identifies multiple chromosomal regions influencing serum lipid levels in the population on the Samoan islands

Abstract

Abnormal lipid levels are important risk factors for cardiovascular diseases. We conducted genome-wide variance component linkage analyses to search for loci influ-

Genetic loci for blood lipid levels identified by linkage and association analyses in Caribbean Hispanics

“…In addition to the signifi cant linkage on 7p12 and 16q23, suggestive linkage was found on 15q23 for TG, 19q12 for TC and LDL-C, and 20p12 for LDL-C. Among these three regions, 19q has been linked to lipid quantitative traits with the most consistent linkage evidence in the previous reports, with LOD scores ranging from 1.9 to 5.7 in the region at 50-70 cM among various populations ( 5,13,16,(53)(54)(55)(56)(57) ( Table 3 ). Similarly, 15q has previously been implicated in several genome scans of lipid-related traits, with LOD scores from 1.8 to 4.2 in the region at 61-72 cM among various populations ( 17,(58)(59)(60)(61)(62) ( Table 3 ).…”

Cardiovascular disease risk factors and DNA methylation at theLINE-1repeat region in peripheral blood from Samoan Islanders

“…1 Although these behavioral factors are linked to obesity and obesityrelated diseases, genetic factors have also been shown to play an important role in Samoan obesity and obesity-related risk factors. [3][4][5][6] Lower levels of LINE-1 methylation in peripheral blood have been previously associated with risk of developing noncommunicable conditions, the most well-explored of these being cancer, although recent research has begun to link altered LINE-1 methylation and cardiovascular disease. We examined the relationship between LINE-1 methylation and factors associated with metabolic and cardiovascular diseases through quantitative bisulfite pyrosequencing in DNA from peripheral blood samples from participants of the Samoan Family Study of Overweight and Diabetes (2002-03).…”

“…Additionally, these findings strongly argue the need for further research, particularly including prospective studies, in order to understand the relationship between LINE-1 DNA methylation measured in blood and risk factors for cardiovascular disease. Although certain genetic loci have been associated with obesity phenotypes in Samoans, [3][4][5][6] studies examining potential links of epigenetic alterations with these extreme metabolic phenotypes are currently lacking in this population.…”

A fourth locus for autosomal dominant hypercholesterolemia maps at 16q22.1

“…None of the recent genome-wide association or linkage studies [21][22][23][24][25][26] identified any loci fulfilling our two search criteria: (1) affecting LDL (only lipoprotein elevated in the HCHOLA4 families) and (2) localized within positions 64 687 100-72 127 000 bp at 16q22. Three genome-wide association studies established an association between loci localized within the HCHOLA4 locus at 16q22.1 reported in this study, and variation in HDL concentrations.…”