Abstract: Objective To investigate the gene polymorphisms of clopidogrel-related cytochrome P450 family member 2C19 (CYP2C19) in patients with cardiovascular and cerebrovascular diseases in the Chaozhou region, China. Methods The patients with cardiovascular and cerebrovascular diseases who attended our hospital from October 2017 to October 2022 and were given oral administration of clopidogrel were enrolled as subjects in this study. RT-PCR was used to detect CYP2C19 gene polymorphisms, and DNA sequencing was used for validation. The distribution of genotype and allele frequencies was analyzed for patients categorized as extensive, moderate, and poor metabolizers, and the differences in genotype frequencies were compared between male and female patients. Results Among the 621 patients, there were 260 cases (41.87%) categorized as CYP2C19 extensive metabolizers (*1/*1), 267 cases (43.00%) categorized as moderate metabolizers (*1/*2, *1/*3), and 94 cases (15.13%) categorized as poor metabolizers (*2/*2, *2/*3, *3/*3), and the allele frequencies of CYP2C19*1, CYP2C19*2, and CYP2C19*3 were 63.37%, 30.68%, and 5.96%, respectively. There was no significant difference in the frequency of CYP2C19 genotypes between the male and female patients (P >0.05). Conclusion The prevalence rates of the extensive metabolism genotype of the clopidogrel-related CYP2C19 gene and CYP2C19*1 allele among patients with cardiovascular and cerebrovascular diseases in Chaozhou is slightly lower than those in other regions across China. The distribution of CYP2C19 genotype frequencies is not associated with sex. CYP2C19 genotype should be determined for patients with cardiovascular and cerebrovascular diseases before clopidogrel treatment, which can help to formulate reasonable and safe individualized treatment strategies in clinical practice.

Key words: Cardiovascular and cerebrovascular diseases, Clopidogrel, CYP2C19, Chaozhou region