Eating disorders, serotonin transporter polymorphisms and potential treatment response

Area of Science:

• Genetics and Psychiatry
• Pharmacogenetics
• Eating Disorder Research

Background:

• Eating disorders like anorexia nervosa, bulimia nervosa, and binge eating disorder share clinical features and have a significant genetic component (50-70% heritability).
• Serotonin system dysfunction is implicated in eating disorders, with reduced serotonin transporter (5-HTT) availability observed in some patients.
• The SLC6A4 gene, encoding 5-HTT, has a common promoter polymorphism (S/L alleles) potentially influencing susceptibility and treatment response.

Purpose of the Study:

• To investigate the association between the SLC6A4 gene polymorphism and anorexia nervosa risk.
• To evaluate the potential of SLC6A4 genotyping for guiding selective serotonin reuptake inhibitor (SSRI) pharmacotherapy in eating disorders.

Main Methods:

• A meta-analysis was conducted on four independent samples assessing the frequency of the SLC6A4*S allele in anorexia nervosa patients.
• Review of existing literature on serotonin transporter genetics and SSRI treatment in eating disorders.

Main Results:

• The meta-analysis revealed that the SLC6A4*S allele is a significant risk factor for anorexia nervosa (OR = 1.38, 95% CI 1.16-1.72).
• Approximately 50% of patients with eating disorders do not respond to SSRIs, highlighting the need for personalized treatment.

Conclusions:

• The SLC6A4*S allele represents a moderate genetic risk factor for developing anorexia nervosa.
• SLC6A4 genotyping could enable personalized SSRI prescribing, improving treatment efficacy for patients with eating disorders.
• Pharmacogenetic insights, including CYP450 variations, are crucial for optimizing antidepressant therapy in eating disorders.