Table 1 Genetic polymorphisms and their impact on clopidogrel response

CYP2C19*2 and *3

Increased clopidogrel resistance

Chinese patients^11,12

Stroke recurrence¹⁴

Risk of stent thrombosis¹⁵

Cardiovascular events^16,17

CYP2C19*17

Strongly linked to an enhanced response to clopidogrel

German patients¹⁸ and Caucasian ICPC subjects¹⁹

High risk of bleeding^18,19

No significant association was shown with platelet inhibition or risk of HPR

Chinese patients²⁰

No effect on post-PCI²⁰

ABCB1 (C3435T)

Connected to clopidogrel hyporesponsiveness

Chinese patients⁴⁶

MACEs^46,47

Not strongly associated with clopidogrel resistance

It is still highly debatable whether the ABCB1 C3435T gene polymorphism influences the antiplatelet effect of clopidogrel

Croatian⁴⁸, Chinese^12,49 and Iranian Patients⁵⁰

NA

CES1 G143E (rs71647871)

Associated with higher plasma concentrations of clopidogrel-active metabolite, and hence may enhance antiplatelet activity

Chinese patients⁵²

NA

CES1 (rs2244613)

Increased the level of residual platelet reactivity and risk of clopidogrel resistance

Russian patients⁵⁴

NA

No effect on the effectiveness of clopidogrel

There was still a lack of relevant studies and inconsistent results

In Egyptians⁵⁵

Not associated with the risk of MACEs⁵⁵

PON1 192Q

Decreased levels of the active metabolite clopidogrel

In the European population⁵⁶

Stent thrombosis⁵⁶

No effect on platelet function and clopidogrel efficacy

In Chinese patients¹³ and Korean patients⁵⁷

Strongly linked to poor cardiovascular outcomes⁵⁷

PON1 192 R

High risk of clopidogrel resistance

In Chinese patients^13,58

No association with clinical outcomes was detected⁵⁸

PCI⁵⁹

There is no effect on the antiplatelet or pharmacokinetic properties of clopidogrel.

It is still unclear which allele, Q or R, is associated with CR

In TRITON-TIMI 38 trial⁶⁰

NA

P2RY12 T744C

Effect on clopidogrel resistance or high on-treatment platelet reactivity

In Chinese patients⁶¹

MACEs and PCI⁶¹

No correlation with on clopidogrel resistance and high platelet reactivity.

Research indicates inconsistencies in the findings

A meta-analysis study was conducted in French, Americans, Chinese, Croatian, Egyptian, and the Czech Republic populations⁶².

Chinese patients^63,64

NA

P2RY12 C34T and G52T

Reduced clopidogrel responsiveness.

Results were not direct enough to guide clinical care

In Chinese patients^61,65

Cardiovascular events⁶⁶