scholarly journals A Chromosome 11q Quantitative-Trait Locus Influences Change of Blood-Pressure Measurements over Time in Mexican Americans of the San Antonio Family Heart Study

2007 ◽  
Vol 81 (4) ◽  
pp. 744-755 ◽  
Author(s):  
Sue Rutherford ◽  
Guowen Cai ◽  
Juan C. Lopez-Alvarenga ◽  
Jack W. Kent ◽  
V. Saroja Voruganti ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Quantitative Trait Locus ◽  
Quantitative Trait ◽  
Mexican Americans ◽  
San Antonio ◽  
Pressure Measurements ◽  
Family Heart Study ◽  
Heart Study ◽  
Trait Locus ◽  
Over Time

scholarly journals A Quantitative Trait Locus on Chromosome 5p Influences D-Dimer Levels in the San Antonio Family Heart Study

2010 ◽  
Vol 2010 ◽  
pp. 1-6
Author(s):  
V. P. Diego ◽  
L. Almasy ◽  
D. L. Rainwater ◽  
M. C. Mahaney ◽  
A. G. Comuzzie ◽  
...  
Keyword(s):  
Quantitative Trait ◽  
Mexican Americans ◽  
San Antonio ◽  
Lod Score ◽  
Family Heart Study ◽  
Heart Study ◽  
A Genome ◽  
Increased Risk ◽  
Chromosome 5P ◽  
D Dimer

Background. D-dimer is associated with increasing severity of atherosclerosis and with increased risk of a cardiovascular disease (CVD).Methods and Results. To better understand this risk factor, we performed a genome scan on 803 (301 males and 502 females) Mexican Americans in the San Antonio Family Heart Study (SAFHS). The SAFHS is ideal for the discovery of quantitative trait loci (QTLs) influencing CVD because CVD risk factors are prevalent in Mexican Americans of San Antonio and because the study design involves large families, which is optimal for QTL discovery. D-dimer levels were normalized in our study. We found that D-dimer levels were heritable, at about 23% heritability (P≈.00001). In a linkage analysis employing 432 microsatellite markers, we found strong evidence of a QTL on chromosome 5p with a lod score of 3.32 at 21 centiMorgans (cM). We also found suggestive evidence of a QTL on chromosome 2q with a lod score of 2.33 at 207 cM.Conclusions. To our knowledge, the putative QTL on chromosome 5p is novel. The possible QTL on chromosome 2q is discussed in relation to a recent report of linkage of a related hemostatic factor to the same location. These results warrant further investigation.

Replacement of α1-Na-K-ATPase of Dahl rats by Milan rats lowers blood pressure but does not affect its activity

2001 ◽  
Vol 7 (2) ◽  
pp. 171-177 ◽  
Author(s):  
SERGEI N. ORLOV ◽  
JULIE DUTIL ◽  
PAVEL HAMET ◽  
ALAN Y. DENG
Keyword(s):  
Blood Pressure ◽  
Quantitative Trait Locus ◽  
Atpase Activity ◽  
Quantitative Trait ◽  
Chromosome Region ◽  
Homologous Region ◽  
Congenic Strains ◽  
Baseline Activity ◽  
Trait Locus

Both linkage and use of congenic strains have shown that a chromosome region near the gene for the Na-K-ATPase α1-subunit ( Atp1a1) contained a quantitative trait locus (QTL) for blood pressure (BP). Currently, two congenic strains, designated S.M5 and S.M6, were made by replacing a segment of the Dahl salt-sensitive SS/Jr (S) rat by the homologous region of the Milan normotensive rat (MNS). In S.M5, the gene for Atp1a1 is from the MNS strain; whereas in S.M6, Atp1a1 is from the S strain. The baseline activity of the α1-Na-K-ATPase and its stoichiometry were evaluated by an assay of ouabain-sensitive inwardly and outwardly directed 86Rb and 22Na fluxes in erythrocytes. The two congenic strains showed a similar BP, but both had a BP lower than that of S rats ( P < 0.0001). Neither the α1-Na-K-ATPase activity nor its stoichiometry was affected by the substitution of the Atp1a1 alleles of S by those of MNS. Thus the BP-lowering effects observed in S.M5 and S.M6 could not be attributed to the α1-Na-K-ATPase activity or its stoichiometry. Atp1a1 is not supported as a candidate to be a BP QTL.

Complete and overlapping congenics proving the existence of a quantitative trait locus for blood pressure on Dahl rat chromosome 17

2005 ◽  
Vol 21 (1) ◽  
pp. 112-116 ◽  
Author(s):  
Myrian Grondin ◽  
Vasiliki Eliopoulos ◽  
Raphaelle Lambert ◽  
Yishu Deng ◽  
Anita Ariyarajah ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Quantitative Trait Locus ◽  
Quantitative Trait ◽  
Congenic Strain ◽  
Chromosome 17 ◽  
Congenic Strains ◽  
Genome Wide ◽  
A Genome ◽  
Trait Locus ◽  
Negative Controls

Linkage studies suggested that a quantitative trait locus (QTL) for blood pressure (BP) was present in a region on chromosome 17 (Chr 17) of Dahl salt-sensitive (DSS) rats. A subsequent congenic strain targeting this QTL, however, could not confirm it. These conflicting results called into question the validity of localization of a QTL by linkage followed by the use of a congenic strain made with an incomplete chromosome coverage. To resolve this issue, we constructed five new congenic strains, designated C17S.L1 to C17S.L5, that completely spanned the ±2 LOD confidence interval supposedly containing the QTL. Each congenic strain was made by replacing a segment of the DSS rat by that of the normotensive Lewis (LEW) rat. The only section to be LL homozygous is the region on Chr 17 specified in a congenic strain, as evidenced by a total genome scan. The results showed that BPs of C17S.L1 and C17S.L2 were lower ( P < 0.04) than that of DSS rats. In contrast, BPs of C17S.L3, C17S.L4, and C17S.L5 were not different ( P > 0.6) from that of DSS rats. Consequently, a BP QTL must be located in an interval of ∼15 cM shared between C17S.L1 and C17S.L2 and unique to them both, as opposed to C17S.L3, C17S.L4, and C17S.L5. The present study illustrates the importance of thorough chromosome coverage, the necessity for a genome-wide screening, and the use of “negative” controls in physically mapping a QTL by congenic strains.

Two closely linked interactive blood pressure QTL on rat chromosome 5 defined using congenic Dahl rats

2002 ◽  
Vol 8 (2) ◽  
pp. 81-86 ◽  
Author(s):  
Michael R. Garrett ◽  
John P. Rapp
Keyword(s):  
Blood Pressure ◽  
Quantitative Trait Locus ◽  
Quantitative Trait ◽  
Congenic Strain ◽  
Major Effect ◽  
Large Region ◽  
Chromosome 5 ◽  
Low Blood Pressure ◽  
Trait Locus

Previously we reported the construction of a congenic strain, S.LEW( 5 ), spanning a large region of rat chromosome 5. The Lewis (LEW) strain was the donor, and the Dahl salt-sensitive (S) strain was the recipient. The congenic strain included a blood pressure quantitative trait locus (QTL). In the present work, a series of nine congenic substrains were constructed from S.LEW( 5 ) which defined two closely linked blood pressure QTL in the region previously thought to contain only one. LEW low-blood-pressure alleles at both QTL were required for a major effect on blood pressure. Neither LEW allele alone had a significant effect on blood pressure. The two QTL were localized to regions 6.3 and 4.6 cM, and these were 1.0 cM apart.

Sign in / Sign up

Export Citation Format

Share Document