Although one cross-sectional study revealed no association between the genetic variants of MTHFR and metabolic parameters in first-episode patients with schizophrenia taking short-term antipsychotics (mean, 6 days) [29], two longitudinal follow-up studies found that those with MTHFR 677CC gained more body weight or exhibited a more significant increase in BMI compared with MTHFR 677T carriers among first-episode patients with schizophrenia following antipsychotic treatment [24,25]. The gene discussed is MTHFR; the disease is schizophrenia.