Objectives To investigate the correlation between C171T mutation of the potassium inwardly-rectifying channel, subfamily J, member 5 (KCNJ5) gene, and the hypokalemic primary aldosteronism (PA).

Methods A total of 364 patients with PA were classified into hypokalemic group (n = 115) and normokalemic group (n = 249). The C171T mutation of KCNJ5 gene in all subjects was genotyped by TaqMan polymerase chain reaction (TaqMan PCR). The correlation between C171T mutation of KCNJ5 gene and hypokalemic PA was analysed.

Results The C171T mutation was genotyped successfully in all subjects and was in Hardy-Weinberg equilibrium (P > 0.05). The hypokalemic and normokalemic PA groups showed statistically significant differences in the distributions of genotypes, alleles, and dominant model models of C171T mutation in overall and female patients (P < 0.05). Logistic regression analysis showed that, after adjusting for age, smoking, alcohol consumption and BMI, the CT + TT genotype of C171T mutation was identified as a risk factor of PA by dominant modelling (OR = 2.50, 95% CI: 1.17-5.35, P = 0.018). In female PA patients, the serum potassium level was significantly reduced, while serum aldosterone concentration was significantly increased in (CT + TT) genotype group compared with those in CC genotype group (all P <0.05).

Conclusions The C171T mutation of KCNJ5 gene is associated with the female hypokalemia PA.