QUANTITATIVE TRAIT LOCI ON CHROMOSOME-1 AND CHROMOSOME-4 AFFECT LIPIDPHENOTYPES IN THE RAT

The spontaneously hypertensive rat (SHR/Mol) and the spontaneously dia betic BB/OK rat were crossed, and the F1 hybrids were backcrossed onto the BB/OK rat in order to search for quantitative trait loci (QTL) af fecting serum total cholesterol and triglycerides on chromosomes 1, 3, 4, 10, 13, 18, and X. On chromosome 4 a QTL for triglyceride levels ( lod score 3.3) was found within the region flanked by the D4Mit9 and I l-6 markers. Suggestive linkage (lod score 1.9) was found for total ch olesterol on chromosome 4 at the Spr locus. Also, on chromosome 1 sugg estive linkage for both investigated traits was found at marker D1Mit1 4 (lod score 1.9 for triglycerides, 2.1 for total cholesterol). The re sults of the study could contribute to the explanation of the genetic basis of lipid abnormalities, which are a common feature of pathologic al disorders such as coronary heart disease, hypertension, or noninsul in-dependent diabetes. (C) 1998 Academic Press.