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Updated: Jul 18, 2026

A Method to Study the C924T Polymorphism of the Thromboxane A2 Receptor Gene
Published on: April 1, 2019
ABCB1 C3435T polymorphism influences methotrexate sensitivity in rheumatoid arthritis patients
R Takatori1, K A Takahashi, D Tokunaga
1Dept. of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan. r-taka@koto.kpu-m.ac.jp
Objective:
Methotrexate (MTX) is most widely used for the treatment of rheumatoid arthritis (RA). However, it has certain drawbacks with regard to individual differences in its therapeutic effects as well as the differences in the patients' response to MTX therapy. We investigated whether multi-drug resistance-1 (ABCB1) C3435T, reduced folate carrier-1 (RFC1) G80A, 5-aminoimidazole-4-carboxamide ribonucleotide transformylase (ATIC) C347G and a 6bp-deletion polymorphism in the 3'-untranslated region of the thymidylase synthase (TYMS) gene are predictive of MTX sensitivity and its adverse effects.
Methods:
Patients whose last maintenance dosage of MTX was
Results:
There were no significant differences in MTX sensitivity among the genotypes of RFC1, ATIC and TYMS genes. ABCB1 3435TT cases included statistically significantly more non-responders than 3435CC cases according to univariate analysis (crude odds ratio (OR) = 8.91, p = 0.001) and multivariate analysis (adjusted OR = 8.78, p = 0.038). There were no significant differences in MTX toxicity among the genotypes of all the genes.
Conclusion:
These results suggested that the genetic diagnosis of ABCB1 C3435T can be applied to determine MTX sensitivity for the treatment of RA patients. However, further pharmacokinetics studies are required in this regard.
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