Toxicity biomarker predicts response to arthritis therapy
Prague – Czech researchers from Charles University in Prague have discovered a molecular biomarker that helps to predict toxicity and a higher risk for adverse effects in children with juvenile arthritis that are treated with methotrexate (J Rheumatol. 2010 Jul 1.). Although the C677T gene variant of the enzyme methylenetetrahydrofolate reductase (MTHFR) did not allow differentiation of responders and non-responders in a study on 69 volunteers, it was a clear indicator for methothrexate toxicity. The frequency of the 677T allele was elevated significantly in patients with adverse effects (52.4% vs 20.9%). Thus, MTHFR genotyping can be used to identify patients with a 55% higher risk for showing adverse effects to methotrexate therapy.