Decreased serum levels of transforming growth factor-β1 in patients with autism

Background: The neurobiological basis for autism remains poorly understood. Given the key role of transforming growth factor-beta 1 (TGF-beta 1) in brain development, we hypothesized that TGF-beta 1 plays a role in the pathophysiology of autism. In this study, we studied whether serum levels of TGF-beta 1 are altered in patients with autism. Methods: We measured serum levels of TGF-beta 1 in 19 male adult patients with autism and 21 age-matched male healthy subjects using enzyme-linked immunosorbent assay (ELISA). Results: The serum levels (7.34 +/- 5.21 ng/mL(mean +/- S.D.))of TGF-beta 1 in the patients with autism were significantly (z = -5.106, p < 0.001) lower than those (14.48 +/- 1.64 ng/mL (mean +/- S.D.)) of normal controls. However, there were no marked or significant correlations between serum TGF beta 1 levels and other clinical variables, including Autism Diagnostic Interview-Revised (ADI-R) scores, Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), aggression, Theory of Mind, and Intellectual Quotient (IQ) in patients. Conclusions: These findings suggest that decreased levels of TGF+beta 1 may be implicated in the pathophysiology of autism. (c) 2006 Elsevier Inc. All rights reserved.