Meta-analysis of data from the Psychiatric Genomics Consortium and additional samples supports association of CACNA1C with risk for schizophrenia.
Recently, numerous genome-wide association studies (GWASs) have identified numerous risk loci for schizophrenia, but follow-up studies are still essential to confirm those results. Therefore, we followed up on top GWAS hits by genotyping implicated loci in additional schizophrenia family samples from our own collection. Five-hundred thirty-six Asian families (comprising 1633 members including 698 schizophrenics) were genotyped in this study. We analyzed 12 single nucleotide polymorphisms (SNPs) in strongly implicated candidate genes revealed by GWASs and their follow-up studies. We then used meta-analysis to combine our results with those of the Schizophrenia Working Group of the Psychiatric Genomics Consortium (PGC). In our newly genotyped samples, there were no significant associations of any of the 12 candidate SNPs with schizophrenia; however, all genome-wide significant results from the schizophrenia PGC analysis were maintained after combination with our new data by meta-analysis. One SNP (rs4765905 in CACNA1C) showed a stronger effect and decreased p-value (5.14e-17) after meta-analysis relative to the original PGC results, with no significant between-study heterogeneity. The findings of this study support the significant results in the PGC, especially for CACNA1C. The sample size in our study was considerably smaller than that in the PGC-SCZ study; thus, the weights carried by our samples in the meta-analysis were small. Therefore, our data could not vastly reduce PGC association signals. However, we considered that the well replicated results from the PGC hold up in our new samples, and may suggest that the top hits from the PGC are generalizable, even to other ancestral groups.
Division of Psychiatry, Department of Psychiatry, Nihon University, School of Medicine, Tokyo, Japan.
Sakae
S
Takahashi
Department of Psychiatry and Behavioral Sciences and Department of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NY, USA.
Stephen J
SJ
Glatt
Division of Psychiatry, Department of Psychiatry, Nihon University, School of Medicine, Tokyo, Japan.
Makoto
M
Uchiyama
Department of Psychiatry and Behavioral Sciences and Department of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NY, USA.
Stephen V
SV
Faraone
Center for Behavioral Genomics, Department of Psychiatry, & Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA, USA; Harvard Institute of Psychiatric Epidemiology and Genetics, Harvard School of Public Health, Boston, MA, USA. Electronic address: mtsuang@ucsd.edu.
Ming T
MT
Tsuang
D044466:Asian People / Q000235:genetics; D020746:Calcium Channels, L-Type / Q000235:genetics*; D005190:Family; D020022:Genetic Predisposition to Disease; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D012306:Risk; D012559:Schizophrenia / Q000235:genetics*
C079146:CACNA1C protein, human; D020746:Calcium Channels, L-Type
CACNA1C; Follow-up study; Genome-wide association study; Meta-analysis; PGC; Schizophrenia