Renal function in relation to three candidate genes.

Abstract

We recently found that femoral intima media thickness, as well as the incidence of hypertension, is influenced by genes encoding the angiotensin-converting enzyme (ACE; insertion/deletion [I/D]) polymorphism, alpha-adducin (Gly460Trp), and aldosterone synthase (-344C/T). By interfering with blood pressure or sodium homeostasis, these genetic polymorphisms also may change renal function. We therefore investigated serum creatinine level, calculated and measured creatinine clearances, and 24-hour urinary protein excretion in subjects previously genotyped for these three polymorphisms. The 1,454 participants drawn at random from the population (64.3% of those invited) were aged 43.4 years and included 744 women (51.2%). Blood pressure, measured by study nurses at subjects' homes, averaged 123/76 mm Hg. Mean values were 90 micromol/L for serum creatinine; 84 and 88 mL/min/1.73 m(2) for calculated and measured (n = 855) creatinine clearances, respectively; and 90 mg/d of protein for proteinuria (n = 556). The prevalence of mild renal dysfunction (creatinine clearance </= 60 mL/min/1.73 m(2)) was nearly 11%. In single-gene analyses with adjustment for significant covariables, the risk for mild renal dysfunction was positively associated with the ACE D allele. However, multiple-gene analyses showed that these associations were restricted to carriers of the mutated alpha-adducin Trp allele (40.1% of all subjects). Findings remained similar after hypertensive patients and women on hormonal therapy were excluded. In this phenotypically more homogeneous subgroup, serum creatinine level was 3.6 micromol/L (P = 0.02) and relative risks for mild renal dysfunction and proteinuria were 1.7-fold (P < 0.001) and 26% (P = 0.02) greater in ACE D subjects than ACE II homozygotes, respectively. The aldosterone synthase T allele did not strengthen genetic associations with the ACE D allele considered alone or in combination with the alpha-adducin Trp allele. Thus, in the present cross-sectional analysis, renal function was slightly but consistently impaired when both the ACE D and alpha-adducin Trp alleles were present. These findings, together with experimental studies and our previous reports on femoral intima media thickness and the incidence of hypertension, constitute a growing body of evidence delineating a clinical entity genetically determined by the risk-carrying ACE D and alpha-adducin Trp alleles.

• Authors: J G Wang, J A Staessen, L Tizzoni, E Brand, W H Birkenhäger, R Fagard, S M Herrmann, G Bianchi
• Journal: American journal of kidney diseases : the official journal of the National Kidney Foundation (Am J Kidney Dis) Vol. 38 Issue 6 Pg. 1158-68 (Dec 2001) ISSN: 1523-6838 [Electronic] United States
• PMID: 11728946 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Calcium Channels
• Calmodulin-Binding Proteins
• TRPC Cation Channels
• adducin
• Creatinine
• Peptidyl-Dipeptidase A

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Calcium Channels (genetics)
• Calmodulin-Binding Proteins (genetics)
• Child
• Creatinine (blood)
• Cross-Sectional Studies
• Female
• Gene Frequency
• Genotype
• Humans
• Hypertension (genetics)
• Kidney Function Tests
• Male
• Middle Aged
• Peptidyl-Dipeptidase A (genetics)
• Polymorphism, Genetic
• Proteinuria (genetics)
• TRPC Cation Channels
• White People (genetics)