Background: In a genome scan for familial combined hyperlipidemia (FCHL), a locus contributing to systolic blood pressure (SBP) has been identified on chromosome 4, containing the a-adducin gene (ADD1). In previous studies, an association has been found between the alpha-adducin Gly460Trp polymorphism and salt-sensitive hypertension. In this study, we investigated the association between the a-adducin Gly460Trp polymorphism and blood pressure in FCHL patients.
Methods: A total of 79 unrelated patients with FCHL and 121 unrelated controls (spouses) were recruited for the study. Blood pressure was measured in a standardized fashion, with the subject in sitting position after 10 min of rest. The alpha-adducin Gly460Trp polymorphism was detected by mutagenically separated polymerase chain reaction.
Results: The genotype frequencies of both FCHL patients and controls were in Hardy-Weinberg equilibrium. The alpha-adducin Gly460Trp polymorphism showed a significant association with FCHL, the number of subjects carrying a 460Trp allele was significantly higher in patients compared with controls (53% v 33%, chi2 = 8.0, P = .018). In FCHL patients carrying at least one 460Trp allele, SBP was significantly higher compared with patients homozygous for the 460Gly allele (140 mm Hg and 130 mm Hg respectively, P = .015).
Conclusions: This study shows that the 460Trp allele is associated with FCHL. Furthermore, SBP is increased in patients carrying the 460Trp allele.