Title: "Analysis of regional differences in the expression frequency of salt-sensitive genes in Japan"

OBJECTIVES: To investigate the regional differences of allele frequency of salt-sensitive genes in Japan. METHODS: This was an observational study, in which a total of 20,981 Japanese men and women aged ≥ 20 years were enrolled from 78 rural and suburban areas of 30 prefectures in Japan between 2004 and 2008. Based on their place of residence, the enrolled subjects were divided into 4 groups, namely Northern Japan (Hokkaido and Tohoku regions), Eastern Japan (KantoKoshinetsu region), Western Japan (Chubu, Kinki, Chugoku, and Shikoku regions), and Southern Japan (Kyushu). Allele appearance frequency of salt-sensitive genes which wereα-Adducin 1 (ADD1) , Angiotensin II , Angiotensin II receptor of type 1, Guanine nucleotide binding protein, β polypeptide 3 (GNB3) were compared among the 4 groups. RESULTS: Significant differences were observed in the genotype frequency of ADD1 and GNB3. CONCLUSIONS: In Japan, among the evaluated salt-sensitive genes, ADD1 and GNB3 have significant regional differences in frequency.