The level of GNE and its relationship with behavioral phenotypes in children with autism spectrum disorder.

Autism spectrum disorder (ASD) is a serious nervous system disease, and the cause is not known. Sialic acid (SA) is an indispensable nutrient for early brain development. In previous study, it was found that the SA level of ASD group was lower than that of control group. However, the reason for this has not well explained. A case-control study was conducted to understand the association between the SA synthase enzyme regulatory gene and ASD. The study sample included 65 ASD children and 64 healthy children. The levels of theGNEgene were measured, which encodes UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE), a key enzyme in SA biosynthesis. The symptom severity, intelligence development level, and behavioral performance of ASD children were estimated. There was a significant difference in the levels ofGNEbetween the ASD and control groups (t= 2.028,P = .045). Moreover, the levels ofGNEwere negatively related to stereotypical behaviors according to the Autism Diagnostic Observation Schedule (ADOS) assessment (r = -0.386,P = .039). However, there is no the correlation between the levels ofGNEand autistic severity. As evaluated through the Social Responsiveness Scale (SRS), the levels ofGNEwere negatively associated with autistic mannerisms scores, social cognition scores and SRS total scores in the children with ASD (r = -0.314,P = .020). These results indicate that theGNEgene may be associated with autism spectrum disorder, and it is also related to autistic behavioral performance, such as stereotypical behaviors, autistic mannerisms, and social cognition ability. Our data suggest that future studies to explore the causal relationship betweenGNEand the etiology of ASD may be needed.