No Association of Variants of the NPY-System With Obsessive-Compulsive Disorder in Children and Adolescents.

Maximilian Franke,Marcel Romanos,Tobias J Renner,Andreas Warnke,Annette Conzelmann,Anna M Werling,Edna Grünblatt,Christoph Wewetzer,Helen Spieles,Susanne Walitza

doi:10.3389/fnmol.2019.00112

Abstract

Obsessive-compulsive disorder (OCD) causes severe distress and is therefore counted by the World Health Organisation (WHO) as one of the 10 most impairing illnesses. There is evidence for a strong genetic underpinning especially in early onset OCD (eoOCD). Though several genes involved in neurotransmission have been reported as candidates, there is still a need to identify new pathways. In this study, we focussed on genetic variants of the Neuropeptide Y (NPY) system. NPY is one of the most abundant neuropeptides in the human brain with emerging evidence of capacity to modulate stress response, which is of high relevance in OCD. We focussed on tag-SNPs of NPY and its receptor gene NPY1R in a family-based approach. The sample comprised 86 patients (children and adolescents) with eoOCD with both their biological parents. However, this first study on genetic variants of the NPY-system could not confirm the association between the investigated SNPs and eoOCD. Based on the small sample size results have to be interpreted as preliminary and should be replicated in larger samples. However, also in an additional GWAS analysis in a large sample, we could not observe an associations between NPY and OCD. Overall, these preliminary results point to a minor role of NPY on the stress response of OCD.

Highlights

Obsessive-compulsive disorder (OCD) has a life-time prevalence of 2%–3.3%, both in adults and children and has its peaks of onset around 12 years and in early adulthood
Patients were included in the study after they had fulfilled the diagnostic criteria for early onset OCD (eoOCD) according to DSM-IV (American Psychiatric Association, 2000), which was valid at the time of recruitment, and ICD-10 (Dilling, 2015)
No transmission disequilibrium was observed for the Neuropeptide Y (NPY)-SNPs

Summary

Introduction

Obsessive-compulsive disorder (OCD) has a life-time prevalence of 2%–3.3%, both in adults and children and has its peaks of onset around 12 years (early onset OCD, eoOCD) and in early adulthood (late onset). The occurring obsessions/compulsions are interfering significantly with the patients’ everyday life and cause severe distress and anxiety. 75% of the patients have at least one comorbidity. In eoOCD these are in particular attention deficit hyperactivity disorder, major depression and anxiety disorders (Fireman et al, 2001). OCD is the fourth most psychiatric disorder and due to its frequently severe impact on affected patients’ lives, the World Health Organisation (WHO) counts OCD to the 10 most impairing illnesses (Karno et al, 1988; Weissman et al, 1994; Lopez and Murray, 1998)

Methods

Results

Conclusion