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Updated: May 15, 2026

Rapid In Situ Hybridization using Oligonucleotide Probes on Paraformaldehyde-prefixed Brain of Rats with Serotonin Syndrome
Published on: September 23, 2015
The serotonin transporter gene locus in late-life major depressive disorder
Davide Seripa1, Francesco Panza, Grazia D'Onofrio
1Geriatric Unit & Gerontology-Geriatric Research Laboratory, Department of Medical Sciences, Institute of Care and Scientific Research Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy. dseripa@operapadrepio.it
Objective:
Polymorphism C in the solute carrier family 6 (neurotransmitter transporter, serotonin), member 4 (SLC6A4) gene has been variously associated with major depressive disorder (MDD). To the best of our knowledge, no data were reported regarding a role of SLC6A4 in late-life MDD. The aim of this study was to explore the possible involvement of the SLC6A4 locus in patients with late-life MDD by means of a haplotype-tagged approach.
Design:
Case-control study.
Setting:
Older patients attending a geriatric unit.
Participants:
A total of 218 patients with late-life MDD (61 men and 157 women) age 65 to 92 years (76.29 ± 6.53 years) and 363 depression-free healthy subjects (156 men and 207 women) age 41 to 65 years (48.33 ± 5.94 years).
Measurements:
Genotyping and haplotype estimation of the three markers rs4795541, rs140701, and rs3813034 spanning a 39-kb block the SLC6A4 locus. Diagnoses of late-life MDD, mild cognitive impairment, Alzheimer disease, vascular dementia, and other dementing diseases were made using current clinical criteria.
Results:
No significant differences were observed in allele or genotype distribution for the three SLC6A4 markers across the study groups. Because the comparison group could not be matched for age, a sensitivity analysis for the misclassification of controls was performed according to different scenarios. For each simulated scenario, the same nonsignificant result was observed. However, the results are limited to late-life MDD that is specifically not associated with cognitive impairment, and there was limited power for detecting very small effect sizes.
Conclusions:
Our findings suggested that the SLC6A4 locus play a minor role, if any, in the pathogenesis of late-life MDD. Also, tempering our conclusions, we were unable to account for population stratification, recurrence or chronicity of depression, nor the influence of coexisting medical, cognitive, and psychosocial stressors.
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