Using the SE of the gradient score, the odds ratios of Alpha-1-antitrypsin (AAT), Interleukin-6 receptor (IL-6r) and connective tissue growth factor (CTGF) showed significant effects to identify schizophrenia for males; AAT, Apolipoprotein B (Apo B) and Sortilin showed significant effects for females. This evidence concerns the gene APOB and schizophrenia.