Background:
Bulimia Nervosa (BN) is a serious Eating Disorder which affects 0.8-2.9% percent of the population. The etiology of BN is largely unknown and concequently there is no curative, although psychotherapy and the antidepressant fluoxetine provide symptomatic relief. Biomarkers for BN could support in understanding the pathophysiology of BN, and potentially in diagnosing, and monitoring of effects of treatment. This review describes genetic and serotonergic biomarkers for BN.

Method:
A literature search using PUBMED (20 June 2017) was done using the following search terms: 1) “Bulimia Nervosa” AND “biomarker” which gave 58 items; 2) BN AND “gene”, “genetic”, and 3) BN AND serotonin, which yielded 342 items. Furthermore, articles of interest were retrieved from the reference lists of the identified articles of the first PUBMED search. The main findings on genetic and serotonergic are summarized.

Results:
Heritability, twin and targeted genetic studies support a gene contribution to the risk of BN. Although there are conflicting findings, 5HTTLPR polymorphism has been found to be linked to BN, especially to the emotional symptoms of the disorder. Several biomarker studies find support for a serotonergic disturbance in BN, and, the Selective Serotonin Reuptake Inhibitor fluoxetine provide symptom relief.

Conclusion:
Recent studies support a genetic contribution to the risk of BN and although there are conflicting findings from targeted gene studies on 5HTTLPR polymorphism in BN, several other findings support a serotonergic disturbance in BN.