Serotonin transporter 5-HTT plays an important role in serotogenic transmisssion. Three polymorphisms, an insertion/deletion and SNP in the promoter region and a variable nucleotide tandem repeat (VNTR) in intron 2, influence expression of the 5-HTT gene. These polymorphisms can contribute to the etiology of many psychiatric disorders.

Associations between a functional variant in the serotonin transporter anxiety-related personality traits were found, as well as the risk of developing depression, alcoholism or suicidal behavior.

The aim of the study was to found possible differences in distribution of variants in three age groups of population.

We examined three polymorphisms at the serotonin transporter protein locus (SLC6A4) in free specific and representative cohorts drawn from the Czech population. These cohorts were stratified according to their age: group A - randomly selected elderly individuals (over 75 years of age), group B young adults in reproductive age (age ranging between 19–45 years) and c) group C - newborns, all with balanced gender representation.

Analysis revealed that elderly individuals were statistically more likely than to carry two copies of the L allele of the lenth polymorphism. This may be due to the protective character of L allele, which is associated with lower susceptibility to bipolar affective disorder, depression, alcohol dependence and neuroticism and can be associated with good mental health and length of living.