Influence of oxytocin level and oxytocin receptor gene expression on the status and severity of autism spectrum disorder in a group of Egyptian children

Background The use of oxytocin (OXT) as a biomarker of autism spectrum disorder (ASD) and its role in the pathophysiology of ASD is still controversial and not straightforward. Objective To evaluate, the association of ASD risk with OXT concentration and the expression of its receptor ( OXTR ) mRNA in a group of children with autism, in addition, to investigating the influence of OXT and OXTR on the status and severity of the disorder in the study ASD group. Patients and methods This study included 30 children diagnosed with ASD, representing the cases group, and a comparable 30 neurotypical children with matched age and sex as a control group. After detailed history taking, pedigree construction, and clinical examination to exclude recognizable syndromes, OXT level and OXTR gene expression were assessed in all included children. Results and conclusion The OXT level in autistic cases was significantly lower than in controls ( P =0.0001). Also, the fold change of OXTR was significantly lower than controls ( P =0.01). Receiver operating characteristic curve analysis showed that at a cut-off point of less than 0.2806, OXTR showed reasonable diagnostic performance with sensitivity, specificity, positive predictive value, and negative predictive value of 53.33, 78.2, 72.7, and 63.2, respectively ( P =0.0067). At a cut-off point of less than or equal to 119 pg/ml, the OXT level showed good diagnostic performance with sensitivity (86.67%), specificity (76.67%), positive predictive value (78.8%), and negative predictive value (85.2%) ( P <0.0001). Our results proved the potential role of OXT plasma measurements and gene expression in diagnosing ASD at optimal cut-off values. These results support the use of OXT as a biomarker for ASD and also as a possible therapeutic option to improve the social behavior of ASD children.