Association Between Polymorphism in the Human Cathepsin L (CTSL1) Promoter with Hypertension in the Uygur, Kazak and Han Populations in China.

Objective: To systemically investigate the association between the polymorphism (rs3118869) in cathepsin Lenzyme gene with hypertension in three ethnic groups (Han, Kazak and Uygur) in China.
Study Design: Case-control study.
Place and Duration of Study: Department of Cardiology, The First Affiliated Hospital, Shihezi Medical College, Shihezi University and Department of Internal Medicine and Genetic Diagnosis Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2013 to May 2014.
Methodology: This case-control study included 1224 patients (422 Uygur, 425 Kazak and 377 Han individuals) with hypertension and 967 healthy unrelated individuals (339 Uygur, 337 Kazak and 291 Han individuals) as controls. The participants came from three ethnic groups (Han, Kazak and Uygur) which were recruited from Xinjiang Province of China. The polymorphism (rs3118869) of the human cathepsin Lgene was genotyped using the TaqMan 5' nuclease assay. Binary logistic regression was built to determine the association of polymorphism with hypertension.
Results: The genotype distribution of polymorphism was not significantly different in three ethnic groups. The rs3118869 polymorphism was significantly associated with Essential Hypertension (EH) in co-dominant model (A/C vs. C/C) in total people (OR = 0.697, 95% CI = 0.520 -0.932, p = 0.015), the same result was obtained in recessive model (C/C + A/C vs. A/A) in total people (OR = 0.689, 95% CI = 0.522 -0.910, p = 0.009). Similar finding of rs3118869 in recessive model (C/C + A/C vs. A/A) was also observed after adjusting the variable to the covariates age (OR = 0.629, 95% CI = 0.464 0853, p = 0.003).
Conclusion: The study results indicate the A-allele of rs3118869 is a protective factor in hypertension.