Increased serum midkine levels in autism spectrum disorder patients.

<bold>Background:</bold> Midkine (MK) is a heparin binding growth factor and is involved in neurogenesis, neural development and neuroprotection. Additionally, MK may contribute to cancer development and pathogenesis of neurodegenerative disorders and schizophrenia. Considering these effects of MK, this study researched whether MK is involved in autism spectrum disorders (ASD) pathogenesis. <bold>Methods:</bold> We evaluated serum MK levels of 38 patients with ASD and 32 healthy control group. MK levels were measured with ELISA, while ASD severity was assessed with Childhood Autism Rating Scale. <bold>Results:</bold> Our data showed that the serum MK concentration in ASD patients (mean ± SD, 11.51 ± 8.53 pg/ml) is significantly higher than healthy controls (mean ± SD, 6.19 ± 3.94 pg/ml) (<italic>p</italic> = 0.007). <bold>Conclusions:</bold> According to these results, MK may play a role in ASD pathogenesis. [ABSTRACT FROM AUTHOR]