Prism software version 5.0 for windows

To compare categorical variables between the groups, we used a chi-square test (χ²) with Yates correction or Fisher's exact test when necessary. The association between the variables was estimated by the odds ratio (OR) with a 95% confidence interval (CI), considering significant p <0.05. The D'Agostino-Pearson test was used to assess the normal distribution of quantitative variables. For comparison of these variables between two groups, a Student’s t test or nonparametric Mann-Whitney test were applied. For three or more groups, the Kruskal-Wallis test or ANOVA were applied when appropriate. GraphPad PRISM software Version 5.0) for Windows (GraphPad Software, San Diego, California, USA) was used for these analyses. Haploview software (version 4.2) was used to test the Hardy-Weinberg equilibrium.

All of the relevant data were presented as means ± standard error means (SEM). One-way analysis of variance (ANOVA) was used for the estimation of statistical significance between each group. For the statistical analysis, GraphPad prism software version 5.0 for Windows (GraphPad Software Inc., La Jolla, CA, United States) was used, where P < 0.05 was considered significant.