Differential effects of 5-HTTLPR genotypes on mood, memory, and
attention bias following acute tryptophan depletion and stress exposure

Firk C, Markus CR.
Department of Clinical Psychological Science,
Faculty of Psychology and Neuroscience,
Maastricht University, P.O. Box 616,
6200, MD, Maastricht,
The Netherlands,
Psychopharmacology (Berl). 2008 Dec 16.


RATIONALE: Polymorphisms of the serotonin transporter gene (5-HTTLPR) may be associated with increased vulnerability to acute tryptophan depletion (ATD) and depression vulnerability especially following stressful life events. OBJECTIVE: The aim of the present study was to investigate the effects of ATD in subjects with different 5-HTTLPR profiles before and after stress exposure on affective and cognitive-attentional changes. MATERIALS AND METHODS: Eighteen subjects with homozygotic short alleles (S'/S') and 17 subjects with homozygotic long alleles (L'/L') of the 5-HTTLPR participated in a double-blind, placebo-controlled, crossover design to measure the effects of ATD on mood, memory, and attention before and after acute stress exposure. RESULTS: ATD lowered mood in all subjects independent of genotype. In S'/S' genotypes, mild acute stress increased depressive mood and in L'/L' genotypes increased feelings of vigor. Furthermore, S'/S' genotypes differed from L'/L' genotypes on measures of attention independent of treatment and memory following ATD. CONCLUSIONS: Polymorphisms of the 5-HTTLPR differentially affect responses to mild stress and ATD, suggesting greater vulnerability of S'/S' carriers to serotonergic manipulations and supporting increased depression vulnerability.
Anxiety disorders
Evolutionary ethics
'Artificial' evolution
Depression genetics
Affective temperaments
Germline genetic engineering
Congenital insensitivity to pain
Dopamine dysfunction and depression
Hyperthymic and depressive temperaments
Affective temperaments and mood disorders
Gene therapy and performance enhancement
Transhumanism (H+): toward a Brave New World?
Serotonin transporter polymorphism, mood disorders and gender


and further reading

BLTC Research
Utopian Surgery?
The Good Drug Guide
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
MDMA: Utopian Pharmacology
Critique of Huxley's Brave New World