Quantitative trait loci with opposing blood pressure effects demonstrating epistasis on Dahl rat chromosome 3

• DOI: 10.1152/physiolgenomics.00084.2003
• Publication Date: 2015-03-03T20:54:52Z
• Authors: Ana Palijan; Julie Dutil; Alan Y. Deng
• Keywords: Congenic; Epistasis; Genetic linkage; Family-based QTL mapping; Chromosome 9

Our previous linkage studies indicated that there might be a blood pressure (BP) quantitative trait locus (QTL) on chromosome 3 (Chr 3) contrasting between the Dahl salt-sensitive (S) strain and Lewis (LEW) strain. To prove then to narrow down segment containing this QTL, five congenic strains have been generated by replacing various segments of S rats with homologous LEW rats. They are designated as S.L1, S.L2, S.L3, S.L4, S.L5, respectively. S.L5 substrains i.e., they contain substitutions smaller sections within large fragment defined S.L1. The construction these was facilitated genome-wide marker screening process. BPs were measured telemetry. S.L2 S.L3 shared Chr in common both showed BP-lowering effect, indicating existence “−BP” QTL alleles from compared S. In contrast, S.L4 involves section no overlap either or BP significantly higher than rats, presence “+BP” Interestingly, combined effect −BP +BP “−” implying is epistatic “+” QTL.