Interaction between blood pressure quantitative trait loci in rats in which trait variation at chromosome 1 is conditional upon a specific allele at chromosome 10.
We have used inbred and congenic rat strains in F(2) segregation studies to discover epistasis in a polygenic model of hypertension. Previously, we have found evidence that the presence of a blood pressure quantitative trait locus (QTL) on chromosome 1 is conditional upon the allele status of chromosome 10. To prove the existence of an epistatic interaction we have analyzed congenic strains for chromosome 1 and 10 carrying high blood pressure QTL alleles from the spontaneously hypertensive rat on a normotensive background of the Wistar-Kyoto (WKY) rat. Additionally, a double congenic strain was developed with both chromosome 1 and 10 high blood pressure QTL alleles on the WKY background. Analysis of variance for blood pressure phenotypes as determined by radiotelemetry showed a significant effect for chromosome 10 but not chromosome 1 QTL alleles and demonstrated a significant interaction between the two loci (P<0.05). The interaction accounted for 5 mmHg of blood pressure. Thus, the identification of epistasis is critical to the understanding of the quantitative nature of blood pressure genetics.
Monti
Jan
J
Max-Delbrück-Center for Molecular Medicine (MDC), Berlin-Buch, Germany.
Plehm
Ralph
R
Schulz
Herbert
H
Ganten
Detlev
D
Kreutz
Reinhold
R
Hübner
Norbert
N
D000483:Alleles; D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure; D002874:Chromosome Mapping; D004195:Disease Models, Animal; D004843:Epistasis, Genetic; D005838:Genotype; D006973:Hypertension / Q000235:genetics*; D008957:Models, Genetic; D010641:Phenotype; D040641:Quantitative Trait Loci; D051381:Rats; D011921:Rats, Inbred WKY