We identified GSTM1 and GSTT1 deletion polymorphisms by multiplex polymerase chain reaction (PCR) in 93 patients with early onset severe mental disorders and 278 control individuals.
To examine glutathione S-transferase (GST) deletion polymorphisms in development of early-onset severe mental disorders, with the hypothesis that patients with GSTM1-null and GSTT1-null genotypes will develop psychotic disorders at a younger age.
Nonetheless, these severe mental disorders have been maintained at a constant relatively high prevalence in the worldwide population across a wide range of cultures and countries despite a strong negative selection against them(2).