Genetic Susceptibility of Obsessive-Compulsive Disorder in The Paediatric Population

Abstract

Obsessive-compulsive disorder (OCD) is a psychiatric disorder involving recurring, unwanted thoughts followed by eliciting ritualistic behaviours to alleviate feelings of distress. Two onsets of OCD exist: early and late. Early-onset (also known as paediatric or childhood) OCD shows greater rates of comorbidities and symptom severity, as well as stronger links to genetics, which are a developing field in OCD etiopathogenesis. An extensive number of twin and family studies have demonstrated heritability of OCD and clustering in families. Although genome-wide association studies (GWAS) are a relatively new addition to the progression of OCD genomics, they have provided initial results on specific candidate genes involved. Currently, the serotonergic, early glutamatergic, and dopaminergic systems possess the main genes implicated in OCD. An epigenetic contribution has also been recently considered in paediatric populations. This review of existing literature primarily focuses on the genetic factors of OCD, particularly its early-onset form.