The chromosomal region, 15q13-q14, including the α7 nicotinic acetylcholine receptor gene, CHRNA7, is a replicated region for schizophrenia. This study fine-mapped genes at 15q13-q14 to determine whether the association is unique to CHRNA7.
Family-based and case–control association studies were performed on Caucasian-non-Hispanic and African-American individuals from 120 families as well as 468 individual patients with schizophrenia and 144 well-characterized controls. Single-nucleotide polymorphism (SNP) markers were genotyped, and association analyses carried out for the outcomes of schizophrenia, smoking, and smoking in schizophrenia.
Three genes were associated with schizophrenia in both ethnic populations: TRPM1, KLF13, and RYR3. Two SNPs in CHRNA7 were associated with schizophrenia in African-Americans, and a second SNP in CHRNA7 was significant for an association with smoking and smoking in schizophrenia in Caucasians.
Results of these studies support association of the 15q13-q14 region with schizophrenia. The broad positive association suggests that more than one 15q gene may be contributing to the disorder, either in combination or through a regulatory mechanism.
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aDepartments of Psychiatry
bPreventive Medicine and Biometrics, University of Colorado Denver
cVeterans Affairs Medical Research Center, Denver, Colorado, USA
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Correspondence to Sherry Leonard, PhD, Department of Psychiatry, University of Colorado at Denver, Mailstop 8344, P.O. Box 6511, Aurora, CO 80045, USA Tel: +1 303 724 4426; fax: +1 303 724 4425; e-mail: Sherry.Leonard@ucdenver.edu
Received September 3, 2010
Accepted July 14, 2011