Serum neurotrophin concentrations in autism and mental retardation: a pilot study

To evaluate the availability of the serum neurotrophins for the diagnosis of the patients with neurodevelopmental disorder, we measured the serum concentration of brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT-4) in the patients diagnosed with autism (n = 18) and mental retardation (n = 20), or healthy controls (n = 16), using enzyme-linked immunosorbent assay. There tended to be a higher concentration of serum BDNF found in the autistic group (P < 0.05 by analysis of variance (ANOVA)) and the mental retardation group (P < 0.001 by ANOVA) compared to the control group. Serum NT-4 concentration tended to be increased in the mental retardation group (P < 0.05 by ANOVA). We conclude that measuring the serum concentration of two neurotrophins, BDNF and NT-4, might be helpful to diagnose or classify disorders such as autism or mental retardation. (C) 2003 Elsevier B.V. All rights reserved.