Fine linkage mapping of the blood pressure quantitative trait locus region on rat chromosome 1

Abstract

To narrow the area known to contain the blood pressure quantitative trait locus (QTL) on rat chromosome 1, we constructed a fine linkage map covering the blood pressure QTL region on the chromosome using 22 genetic markers informative for stroke-prone spontaneously hypertensive rats of the lzumo colony (SHRSP/lzm) and Wistar-Kyoto rats of the lzumo colony (WKY/lzm). Linkage mapping was done by genotyping 626 backcrossed rats from matings between SHRSP/lzm and WKY/lzm. Nineteen genetic markers informative for the two strains were selected from public databases. Two markers were newly isolated by screening a rat genomic library. One marker was mapped using a restriction endonuclease polymorphism. The region between D1Wox29 and D1Smu11 was covered with 22 informative markers placed every 0.6 cM on average. In addition, 6 physiological candidates for a hypertension gene were mapped in this region either by linkage or by radiation hybrid (RH) mapping. This information should be essential for the construction and analysis of congenic strains for this QTL region.