XPNPEP1 and cerebral palsy: Among the genes in strong linkage disequilibrium with this locus are adducin3 (ADD3), which codes for a ubiquitously expressed cytoskeletal protein implicated in cerebral palsy,49 and aminopeptidase P (XPNPEP1), which has been found to be involved in the degradation and maturation of neuropeptides.50 Of the seven other genome-wide significant signals, four were reported in the PGCBD24 and an additional three by Chen et al.26 (Figure 2 and Supplementary Table 5).