As 30 of the 77 proteins analysed have been previously associated with schizophrenia (Supplementary Table 6), it was re-assuring, although not unexpected, that the majority of the selected proteins (12 of 14; Table 3) have been previously associated with schizophrenia30–33 with the most robust finding for increased HPT levels in schizophrenia patients compared to controls30,34–37. This evidence concerns the gene MRS2 and schizophrenia.