Systematic search for mutations in the 14–3-3 η chain gene on chromosome 22 in schizophrenics

The brain-rich 14–3-3 protein regulates synthesis and excretion of bioamine by activating tyrosine and tryptophan hydroxylases, and by exocytosis of catecholamines and serotonin. In humans, at least eight subunits of the 14–3-3 protein family have been isolated. The 14–3-3 η chain gene is located at 22q12.1 to q13.1, one of the chromosome regions identified as possibly linked to schizophrenia. We systematically searched for nucleotide variants in the coding region, 5′ and 3′ untranslated region, and in the exon-intron boundaries of the genomic 14–3-3 η gene in 24 schizophrenics and 24 controls. Two polymorphic sites were found: one in the 5′ untranslated region and one in the 3′ untranslated region. However, no variants predicting amino-acid alterations were observed. Similar allelic and genotypic distributions for both polymorphisms were found in 308 schizophrenics and 135 controls.