alpha-adducin gene and essential hypertension in China

Adducin is a membrane skeletal protein that is involved in the regulation o f membrane ion transport and cellular signal transduction. Essential hypert ension has been linked to alpha -adducin gene locus, and association of a p olymorphism of the gene has been found in some studies, but results of link age or association studies on alpha -adducin gene are controversial among d ifferent populations. This study was designed to examine the linkage betwee n alpha -adducin gene locus and essential hypertension and to reveal the re lationship between an alpha -adducin gene polymorphism (Gly460Trp) and esse ntial hypertension in a Chinese population. For the linkage study, one hund red and six Chinese nuclear families were recruited, including 417 hyperten sive patients in all 474 individuals. Those samples were genotyped at D4S41 2 and D4S3038. The distances between the two microsatellite markers and the alpha -adducin gene locus are less than 3cM. Parametric, non-parametric li nkage (NPL) analyses using the GENEHUNTER software were carried out. Sib tr ansmission-disequilibrium test (S-TDT), as well as transmission-disequilibr ium test (TDT), was also implemented with TDT/S-TDT Program 1.1. Serum leve ls of uric acid, creatinine, blood urea nitrogen (BUN), fasting glucose and lipids were determined as phenotypes. In an association study, 138 hyperte nsive and 121 normotensive subjects were genotyped at Gly460Trp of the alph a -adducin gene to examine a possible association between this polymorphism and blood pressure or other phenotypes. We fail to find the linkage betwee n the two markers and essential hypertension by parametric, NPL analysis or TDT/S-TDT study. With the use of the simple association and the multivaria te logistic regression analyses, we also fail to reveal a significant assoc iation between the Gly460Trp polymorphism in alpha -adducin gene and the bl ood pressure variation, or blood biochemical indices studied. The frequency of the 460Trp allele in Chinese (46-48%) is similar to that found in Japan ese (54-60%) while tile allele frequency is less common in Caucasian (13%-2 3%). These findings suggest that in our Chinese population, alpha -adducin 460Trp variant may not play an important role in the etiology of EH. And th e negative results of linkage and TDT/S-TDT further supports this conclusio n.