Schizophrenia genetics: progress, at last.

The heritability of schizophrenia is well established, and has motivated the search for genetic variation that contributes to susceptibility. Recent progress from both genome-wide association and copy number variant studies have identified risk loci, however, these are at very different ends of the susceptibility spectrum with respect to allele frequency and effect size. It is likely that investigations of common variants have surrendered their full yield, but rare variant exploration is at the very beginning.