Linkage disequilibrium for schizophrenia at the chromosome 15q13-14 locus of the alpha 7-nicotinic acetylcholine receptor subunit gene (CHRNA7)

The transmission/disequilibrium test was used for fine mapping of the linka ge of schizophrenia to the chromosome 15q13-14 region, the site of a candid ate gene, the alpha7 nicotinic acetylcholine receptor subunit gene (CHRNA7) , in parent-child triads from the NIMH Schizophrenia Genetics Initiative fa milies. This candidate gene was identified from neurobiological studies of deficits in schizophrenics of the inhibitory gating of the P50 auditory evo ked potential. The neurobiological deficit was also used as a phenotype for subsequent linkage analysis. In the present study, significant genotype-wi se disequilibrium (P < 0.007) was found at D15S165, a polymorphic simple se quence marker physically located within 1 megabase of both CHRNA7 and a par tially duplicated, expressed sequence that includes exons 5-10 of CHRNA7, R eplication of this result was found in an additional set of families. The r esults support this region as a chromosomal location involved in the geneti c transmission of schizophrenia. Am. J, Med, Genet, (Neuropsychiatr,Genet,) 105: 20-22, 2001, (C) 2001 Wiley-Liss, Inc.