title: Identification of quantitative trait loci for cardiac hypertrophy in two different strains of the spontaneously hypertensive rat.
abstract: Cardiac hypertrophy and left ventricular hypertrophy are known to be substantially controlled by genetic factors. As an experimental model, we undertook genome-wide screens for cardiac mass in F2 populations bred from the stroke-prone spontaneously hypertensive rats (SHRSP) and normal spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) of a Japanese colony. Two F2 cohorts were independently produced: F2(SHRSP x WKY) (110 male and 110 female rats) and F2(SHR x WKY) (151 male rats). The ratio of heart weight to body weight (Hw/Bw) was evaluated at 12 months of age in F2(SHRSP x WKY) after salt-loading for 7 months, and at around 15 weeks of age in F2(SHR x WKY) who had been fed a normal rat chow diet. Subsequent to an initial screen with 251 markers in F2(SHRSP x WKY) male progeny, 170 and 161 markers were selected and characterized in F2(SHRSP x WKY) female progeny and F2(SHR x WKY) male progeny, respectively. Markers from four chromosomal regions showed suggestive or significant linkage to Hw/Bw. The strongest and the most consistent linkage was found in the vicinity of D3Mgh16 on rat chromosome (RNO) 3 (a maximal log of the odds score reached 4.0 to 6.6 across the F2 populations studied). In the other three regions on RNO6, RNO10 and RNO13, the degree of linkage was more prominent in either males or females. These data provide solid evidence for a "principal" RNO3 quantitative trait loci regulating Hw/Bw in SHRSP and SHR, and also suggest the possible presence of sexual dimorphism in regard to genetic susceptibility for cardiac hypertrophy.
authors.affiliation: Department of Gene Diagnostics and Therapeutics, Research Institute, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan.
authors.forename: Hyoe
authors.initials: H
authors.lastname: Inomata
authors.forename: Takehiro
authors.initials: T
authors.lastname: Watanabe
authors.forename: Yoko
authors.initials: Y
authors.lastname: Iizuka
authors.forename: Yi-Qiang
authors.initials: YQ
authors.lastname: Liang
authors.forename: Tomoji
authors.initials: T
authors.lastname: Mashimo
authors.forename: Toru
authors.initials: T
authors.lastname: Nabika
authors.forename: Katsumi
authors.initials: K
authors.lastname: Ikeda
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Yanai
authors.forename: Takanari
authors.initials: T
authors.lastname: Gotoda
authors.forename: Yukio
authors.initials: Y
authors.lastname: Yamori
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
authors.forename: Norihiro
authors.initials: N
authors.lastname: Kato
mesh_terms: D000818:Animals; D006332:Cardiomegaly / Q000235:genetics*; D002874:Chromosome Mapping; D005260:Female; D008040:Genetic Linkage; D005819:Genetic Markers; D006973:Hypertension / Q000235:genetics*; D008297:Male; D040641:Quantitative Trait Loci; D051381:Rats; D011918:Rats, Inbred SHR / Q000235:genetics*; D011921:Rats, Inbred WKY; D013045:Species Specificity
chemical_list: D005819:Genetic Markers