Candidate genes in quantitative trait loci associated with absolute and relative kidney weight in rats with Inherited Stress Induced Arterial Hypertension

Background: The kidney mass is significantly increased in hypertensive ISIAH rats with Inherited Stress Induced Arterial Hypertension as compared with normotensive WAG rats. The QTL/microarray approach was carried out to determine the positional candidate genes in the QTL for absolute and relative kidney weight. Results: Several known and predicted genes differentially expressed in ISIAH and WAG kidney were mapped to genetic loci associated with the absolute and relative kidney weight in 6-month old F2 hybrid (ISIAHxWAG) males. The knowledge-driven filtering of the list of candidates helped to suggest several positional candidate genes, which may be related to the structural and mass changes in hypertensive ISIAH kidney. In the current study, we showed that all loci found for absolute and relative kidney weight didn't overlap with significant or suggestive loci for arterial blood pressure level. So, the genes differentially expressed in ISIAH and WAG kidneys and located in these QTL regions associated with absolute and relative kidney weight shouldn't substantially influence the BP level in the 6 month-old ISIAH rats. However, in some cases, small effects may be suggested. Conclusions: The further experimental validation of causative genes and detection of polymorphisms will provide opportunities to advance our understanding of the underlying nature of structural and mass changes in hypertensive ISIAH kidney.