Serotonin 2A receptor (5-HT2A) gene was implicated to be associated with both schizophrenia and Suicidal behavior due to its role of key neurotransmitter in many physiologic processes. Association studies were reported in different populations, however, a great number of subsequent studies have produced contrary results, possibly reflecting inadequate statistical power. With the Cumulative data in recent years in both European and Asian populations, particularly in Asian populations, it was necessary to carry out a comprehensive analysis of previous findings. The meta-analysis, therefore, combined all English and Chinese studies using multiple research methods published up to July 2005 to give a new picture of the role of the 5-HT2A gene. Compared with significant results reported previously, the current large samples (73 studies in all) failed to find significant association of the T102C polymorphism with either schizophrenia or suicidal behavior. Evidence of significant association was only detected between A-1438G and Suicidal behavior. The current study did not support the association of the 5-HT2A gene with either schizophrenia or suicidal behavior. (c) 2005 Elsevier Inc. All rights reserved.