Lochman et al (2014) state a possible epigenetic link between MTHFR C677T mutations, high homocysteine and schizophrenia. 192 schizophrenic patients were examined alongside 213 controls, with an increased risk of schizophrenia presentation associated both MTHFR 677 CT and TT mutations. The authors also studied the relationship between C677T, COMT and ADRA2A gene mutations. This study did not show an interaction between MTHFR and COMT mutations, but demonstrated a link with the ADRA2A polymorphism. This governs normal presynaptic control of neurotransmitter release from sympathetic and adrenergic neurons in the CNS. Therefore, this study demonstrates a link between both noradrenergic and methylation genetic malfunctioning, leading to the increased risk of schizophrenic development.