Substitution mapping of a blood pressure quantitative trait locus to a 2.73 Mb region on rat chromosome 1.
OBJECTIVE
To improve the localization of a blood pressure quantitative trait locus (BP QTL) on rat chromosome (RNO) 1.


METHODS
Congenic substrains were derived from the progenitor congenic strains S.LEW(D1Mco4X1) and S.LEW(D1Mco4X5) which previously localized a BP QTL (region 2) to a 17cM interval on RNO1. The newly developed congenic substrains, along with control Dahl salt-sensitive (S) rats were fed a 2% NaCl diet for 24 days before their BP was compared by both tail-cuff and radiotelemetry methods.


RESULTS
By comparing BP of these congenic substrains to that of S rats, we have refined the location of the BP QTL2 region to a 2.73 Mb genomic interval that contains 19 annotated genes in the latest rat genome assembly (version 2.1). Slc9a3, the gene encoding the Na(+)/H(+) exchanger 3, originally a candidate gene in the BP QTL2 region, is excluded based on its map location.


CONCLUSIONS
Substitution mapping was used to reduce a BP QTL on RNO1 from 17 centimorgans (cM) to approximately 1.4 cM (= 2.73 Mb). This region now contains 19 annotated rat candidate genes.
Joe
Bina
B
Department of Physiology and Molecular Medicine, Medical College of Ohio, Toledo, OH 43614, USA. bjoe@mco.edu
Garrett
Michael R
MR
Dene
Howard
H
Rapp
John P
JP
D000818:Animals; D020296:Animals, Congenic; D001794:Blood Pressure; D002874:Chromosome Mapping; D016678:Genome; D040641:Quantitative Trait Loci; D051381:Rats; D020303:Rats, Inbred Dahl; D011917:Rats, Inbred Lew / Q000235:genetics