Association Between 5-HTTLPR Polymorphism and Tics after Treatment with Methylphenidate in Korean Children with Attention-Deficit/Hyperactivity Disorder.

Abstract

OBJECTIVES:

The purpose of this study is to examine the relationship between 5-HTTLPR polymorphism (44-bp insertion/deletion polymorphism of serotonin transporter gene) and methylphenidate (MPH) treatment response, as well as the association between the adverse events of MPH treatment and 5-HTTLPR polymorphism in children with attention-deficit/hyperactivity disorder (ADHD).

METHODS:

A total of 114 children with ADHD (mean age 9.08 ± 1.94 years) were recruited from the child psychiatric clinic in a hospital in South Korea. We have extracted the genomic DNA of the subjects from their blood lymphocytes and analyzed 5-HTTLPR polymorphism of the SLC6A4 gene. All children were treated with MPH for 8 weeks, with clinicians monitoring both the improvement of ADHD symptoms and the side effects. We compared the response to MPH treatment and adverse events among those with the genotype of 5-HRRLPR polymorphism.

RESULTS:

There was no significant association between the 5-HTTLPR genotype and the response to MPH treatment in children with ADHD. Subjects with the S/L+L/L genotype tended to have tics and nail biting (respectively, p < 0.001, p = 0.017).

CONCLUSIONS:

The results of this study do not support the association between the 5-HTTLPR polymorphism and treatment response with MPH in ADHD. However, our findings suggest the association between 5-HTTLPR polymorphism and the occurrence of tics and nail-biting as an adverse event of methylphenidate. This may aid in our understanding of the genetic contribution and genetic susceptibility of a particular allele in those ADHD patients with tics or nail biting.

• Authors: Seo Yeon Park, Eun Joo Kim, Keun-Ah Cheon
• Journal: Journal of child and adolescent psychopharmacology (J Child Adolesc Psychopharmacol) Vol. 25 Issue 8 Pg. 633-40 (Oct 2015) ISSN: 1557-8992 [Electronic] United States
• PMID: 26402385 (Publication Type: Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Central Nervous System Stimulants
• SLC6A4 protein, human
• Serotonin Plasma Membrane Transport Proteins
• Methylphenidate

Topics

• Adolescent
• Alleles
• Attention Deficit Disorder with Hyperactivity (complications, drug therapy)
• Central Nervous System Stimulants (adverse effects, therapeutic use)
• Child
• Female
• Genotype
• Humans
• Male
• Methylphenidate (adverse effects, therapeutic use)
• Nail Biting
• Polymorphism, Genetic (genetics)
• Republic of Korea
• Serotonin Plasma Membrane Transport Proteins (genetics)
• Tics (chemically induced, complications, genetics)
• Treatment Outcome