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Updated: May 20, 2026

A Method to Study the C924T Polymorphism of the Thromboxane A2 Receptor Gene
Published on: April 1, 2019
Functional polymorphisms in CYP2C19 & CYP3A5 genes associated with decreased susceptibility for paediatric
Wei-Xing Feng1, Fang Liu, Yi Gu
1Key Laboratory of Major Diseases in Children & National Key Discipline of Pediatrics (Capital Medical University), Ministry of Education, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, affiliated to Capital Medical University, Beijing, China.
Background & Objectives:
Tuberculosis (TB) bacilli ingested by macrophages evade host immune responses by multiple mechanisms including the inhibition of apoptosis. As the cytochrome-P-450 system (CYP) contributes to apoptosis it has been suggested that genetic variation in CYP may be associated with susceptibility to TB infection. This study was carried out to evaluate cytochrome P-450 polymorphisms in Chinese Han children and to investigate the effect of these polymorphisms in paediatric TB.
Methods:
Frequencies for the CYP2C19, CYP3A4, CYP3A5 and CYP2E1 mutated alleles and genotypes were compared between 142 Chinese paediatric TB patients and 150 non-infected controls by real time PCR genotyping on peripheral leukocyte DNA.
Results:
CYP2C19 (636 G>A, rs4986893) A allele and AG genotype were associated with decreased susceptibility to TB (P = 0.006, OR= 0.33, 95% CI: 0.15-0.76; and P = 0.005, OR =0.31, 95% CI: 0.14-0.72 respectively), as were the CYP3A5 (6986A>G, rs776746) G allele and particularly homozygous GG (recessive mode) genotype (P = 0.004, OR=0.61, 95% CI: 0.43-0.85; and P=0.002, OR=0.47, 95% CI: 0.29-0.76).
Interpretation & Conclusions:
The data suggested that CYP2C19 and CYP3A5 polymorphisms affect susceptibility to paediatric TB. Further studies are indicated to confirm and elucidate these observations.
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