Figure 3. Effects of a single nucleotide polymorphism in the promoter of CHRNA7 on P50 sensory gating. The normal subject with more common alleles (-86 C/C) has normal suppression of P50, measured as a low P50 test to conditioning amplitude ratio. The subjects with the polymorphism (-86 C/T) have higher, more abnormal ratios. The physiological abnormality is expressed regardless of whether the subject is normal or has schizophrenia.
Reproduced from reference 9: Leonard S, Gault J, Hopkins J, et al. Association of promoter variants in the α7-nicotinic acetylcholine receptor subunit gene with an inhibitory deficit found in schizophrenia. Arch Gen Psychiatry. 2002;59:1085-1096. Copyright © 2002, American Medical Association.