The gene encoding NRG1 is large, spanning ~1.2 Mb and contains >23 000 single-nucleotide polymorphisms (SNPs) among which ~40 have been associated with schizophrenia.5 Genome-wide association studies have generally, however, only provided modest support with the most recent study implicating rs986110 (P=1.5 × 10−4) with the disorder.6 This may in part be due to genome-wide association study to date focussing exclusively on SNP variation and consequently underestimating the importance of genes, such as NRG1, for which haplotype and microsatellite variation has been demonstrated. This evidence concerns the gene NRG1 and schizophrenia.