The first genetic mutation I’m referring to is: the Val158Met polymorphism.

The COMT gene encodes catechol-O-methyltransferase, an enzyme that breaks down synaptic dopamine (DA) and norepinephrine (NE). The best studied polymorphism of the COMT gene is a single G>A substitution at codon 158 (rs4680), resulting in a valine (Val) to methionine (Met) amino acid change. This Val158Met polymorphism results in a decrease in COMT enzymatic activity, which can be described in a trimodal pattern for three genotypes: high in Val/Val, intermediate in Val/Met, and low in Met/Met.…