OBJECTIVE: To probe into the distribution characteristics and clinical significance of clopidogrel metabolic enzyme CYP2 C19 gene polymorphism in patients with cerebral infarction in Xiamen

so as to further guide clinical individualized and precise medication. METHODS: According to the inclusion exclusion criteria

inpatients in neurology department of Zhongshan Hospital Affiliated to Xiamen University from Jan. 2017 to Aug. 2019 were screened. CYP2 C19 genotype

alleles

phenotypes and other information were collected

and the distribution differences among different genders and ages were analyzed. RESULTS: A total of 425 patients with cerebral infarction were included. Among the six test results

the detection rate of CYP2 C19 * 1/* 1 was the highest（ 39. 06%

166 cases）

and the detection rate of CYP2 C19* 3/* 3 was the lowest（ 0. 47%

2 cases）. The frequency of CYP2 C19*2 and * 3 alleles was 33. 53%（ 285/850） and 5. 53%（ 47/850）

respectively. The proportion of patients with extensive metabolizers（ EM）

intermediate metabolizers（ IM） and poor metabolizers（ PM） was 39. 06%（ 166 cases）

43. 76%（ 186 cases） and 17. 18%（ 73 cases）

respectively. There was no significant difference in the distribution of genotypes and phenotypes between different genders and age groups（ P>0.05）. In patients >75 years

the difference in distribution of EM by gender was statistically significant（ P < 0. 05）. CONCLUSIONS: Mutations of CYP2 C19* 2 alleles are common in patients with cerebral infarction in Xiamen

and the proportion of non-EM patients is relatively high. It is recommended that clopidogrel metabolic enzyme CYP2 C19 gene test should be first performed on conditional patients with cerebral infarction

and pay attention to the detection of platelet aggregation function during treatment

so as to help guide the individualized precise medication of cerebral infarction.