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Serotonin transporter gene polymorphism and the phenotypic heterogeneity of adult ADHD

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Summary

The present study investigates possible associations between the 5-HTT control region polymorphism (5-HTTLPR) with adult ADHD, including subtypes, severity, temperament profile and comorbidities. The polymorphic site was genotyped in 312 adult patients with ADHD and 236 controls, all of them Brazilians of European descent. The interviews followed the DSM-IV criteria, using the K-SADS-E for ADHD and oppositional defiant disorder, SCID-I and MINI for comorbidities and the TCI for temperament dimensions. The 5-HTTLPR polymorphism was not associated with ADHD. Carriers of the S allele presented slightly higher inattention and novelty seeking scores, and a higher frequency of drug dependence. These differences do not persist after correction for multiple comparisons. These results suggest that the 5-HTTLPR polymorphism does not have a direct role in the predisposition to adult ADHD. There is suggestive evidence for a small effect in some behavioral phenotypes related to ADHD.

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Authors and Affiliations

  1. Adult ADHD Outpatient Clinic, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil

    E. H. Grevet, C. A. I. Salgado, A. G. Fischer, K. L. Kalil, M. M. Victor, C. R. Garcia, N. O. Sousa, P. Belmonte-de-Abreu & C. H. D. Bau

  2. Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil

    F. Z. C. Marques & C. H. D. Bau

  3. Departamento de Psiquiatria, Faculdade de Medicina, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil

    P. Belmonte-de-Abreu

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Grevet, E., Marques, F., Salgado, C. et al. Serotonin transporter gene polymorphism and the phenotypic heterogeneity of adult ADHD. J Neural Transm 114, 1631–1636 (2007). https://doi.org/10.1007/s00702-007-0797-2

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