To test the hypothesis, we conducted association studies of GULP1, ABCA1 and ABCA7, located at chromosomes 2, 9 and 19 respectively, with the Irish study of high density schizophrenia families (ISHDSF) and Irish case-control study of schizophrenia (ICCSS) samples and followed up these analyses with targeted replication in multiple independent samples. Here, ABCA1 is linked to schizophrenia.