91 SSLP markers at an average spacing of 15 cM were screened in 207 (BALB/cJ x CBA/CaJ)F2 animals to identify QTLs associated with blood pressure, heart rate, and heart weight. Parental strain BALB/cJ exhibits higher blood pressure, slower heart rate, and increased heart weight compared to parental strain CBA/CaJ.
Bpq6, a previously identified QTL on mouse Chromosome 15, was mapped in this cross.
04.08.2016 Curator Note: Because Bpq6 was previously mapped in J:66987 in 2001 using a (C57BL/6J x A/J)F1 x C57BL/6J mapping population, which differs from the population used here, we consider the current study a separate mapping experiment and have named this QTL Bpq31.
Bpq31 spans 0 cM - 25 cM with peak linkage at D15Mit175 (LOD score = 4.9). CBA/CaJ-derived alleles confer increased blood pressure at this locus.
Bpq7 was mapped in this cross to mouse Chromosome 7. Bpq7 spans 35 cM - 50 cM with peak linkage at D7Mit31 (LOD score = 6.1). BALB/cJ-derived alleles confer increased blood pressure at this locus. Candidate genes for Bpq7 include Adm, Pth, Calca, Scnn1b, and Scnn1g.
Heart rate QTLs Hrq1, Hrq2, and Hrq3 mapped to mouse chromosomes 2, 15, and 1, respectively. Hrq1 spans 60 cM - 80 cM on mouse Chromosome 2 with peak linkage at D2Mit304 (LOD score = 4.0). CBA/CaJ-derived alleles confer increased heart rate with additive inheritance at this locus. Candidate genes proposed for Hrq1 are Chrna1, Chrm4, and Chrm5. Hrq2 spans 20 cM - 35 cM on mouse Chromsome 15 with peak linkage at D15Mit184 (LOD score = 3.1). CBA/CaJ-derived alleles confer increased heart rate with dominant inheritance at this locus. Hrq3 spans 45 cM - 75 cM on mouse Chromosome 1 and was detected by significant interaction with Hrq1 at D1Mit10. Animals homozygous or heterozygous for CBA/CaJ-derived alleles at Hrq3 exhibit increased heart rate in conjunction with a CBA/CaJ-derived allele at Hrq1. Possible candidate genes for Hrq3 are Chrnd and Chrng.
A QTL for heart weight, Hwq1, mapped to 38 cM on mouse Chromsome 14. Hwq1 spans 20 cM - 43 cM with peak linkage at D14Mit67 (LOD score = 2.9).