Functional variants in genes that regulate folate absorption significantly influence treatment response in patients given folate plus vitamin B12 supplementation to improve negative symptoms of schizophrenia, according to a study published online March 6 in JAMA Psychiatry. These findings, the authors say, support a personalized medicine approach for the treatment of negative symptoms in schizophrenia, and possibly other folate interventions in additional clinical areas. Negative symptoms in schizophrenia (apathy, social withdrawal, and loss of emotional expressiveness) are not improved with anti-psychotics and have previously been tied to reduced blood folate levels. Given mandatory folate fortification of grain products in the United States, the authors explain that the benefits of folate supplementation may be less readily detected and clinical response may depend on genotype. In a multicenter clinical trial, 140 stable patients with schizophrenia who chronically displayed symptoms despite anti-psychotic treatment were randomized (2:1) to receive daily, oral supplementation with 2 mg of folic acid and 400 μg of vitamin B12 (n=94) or placebo (n=46). DNA extracted from whole blood samples in 120 consenting participants was genotyped for four variants previously associated with negative symptom severity (FOLH1 484C>T, MTHFR 677C>T, MTR 1298G>A, and COMT 675G>A). The researchers found that in the […]