andidate Gene Polymorphisms in the Serotonergic athway : Influence on Depression Symptomatology n an Elderly Population
ackground: Depressed mood is a major concern in the elderly, with consequences for morbidity and mortality. Previous studies have emonstrated that genetic factors in depression and subsyndromal depressive symptoms are no less important in the elderly than uring other life stages. Variations in genes included in the serotonin system have been suggested as risk factors for various psychiatric isorders but may also serve as candidates for normal variations in mood. ethods: This study included 684 elderly Danish twins to investigate the influence of 11 polymorphisms in 7 serotonin system genes n the mean level of depression symptomatology assessed over several years, reflecting individuals’ underlying mood level. esults: A suggestive association of sequence variations in genes responsible for the synthesis (TPH), recognition (5-HTR2A), and egradation (MAOA) of serotonin with depression symptomatology was found, although the effect was generally restricted to men. We lso found that a specific haplotype in VMAT2, the gene encoding the vesicular monoamine transporter, was significantly associated ith depression symptoms in men (p .007). onclusions: These results suggest that variations in genes encoding the components of serotonin metabolism may influence the basic ood level and that different genetic factors may apply in men and women.