The strongest signal in BD was with rs420259 at chromosome 16p12 (genotype test P=6.3×10-8; Table 3) and the best-fitting genetic model was recessive (Supplementary Table 8). Although recognizing that this signal was not additionally supported by the expanded reference group analysis (see below and Supplementary Table 9) and that independent replication is essential, we note that several genes at this locus could have pathological relevance to BD, (Fig. 5). These include PALB2 (partner and localizer of BRCA2), which is involved in stability of key nuclear structures including chromatin and the nuclear matrix; NDUFAB1 (NADH dehydrogenase (ubiquinone) 1, alpha/beta subcomplex, 1), which encodes a subunit of complex I of the mitochondrial respiratory chain; and DCTN5 (dynactin 5), which encodes a protein involved in intracellular transport that is known to interact with the gene ‘disrupted in schizophrenia 1’ (DISCI)32, the latter having been implicated in susceptibility to bipolar disorder as well as schizophrenia33.