Do Tardive Dyskinesia and l-Dopa Induced Dyskinesia Share Common Genetic Risk Factors? An Exploratory Study
Tardive dyskinesia (TD) in schizophrenia patients treated with antipsychotic medications and l-dopa induced dyskinesia (LID) among Parkinson's disease (PD) affected individuals share similar clinical features. Both conditions are induced by chronic exposure to drugs that target dopaminergic receptors (antagonists in TD and agonists in LID) and cause pulsatile and nonphysiological stimulation of these receptors. We hypothesized that the two motor adverse effects partially share genetic risk factors such that certain genetic variants exert a pleiotropic effect, influencing susceptibility to TD as well as to LID. In this pilot study, we focused on 21 TD-associated SNPs, previously reported in TD genome-wide association studies or in candidate gene studies. By applying logistic regression and controlling for relevant clinical risk factors, we studied the association of the SNPs with LID vulnerability in two independent pharmacogenetic samples. We included a Jewish Israeli sample of 203 PD patients treated with l-dopa for a minimum of 3 years and evaluated the existence or absence of LID (LID+ = 128; LID− = 75). An Italian sample was composed of early LID developers (within the first 3 years of treatment, N = 187) contrasted with non-early LID developers (after 7 years or more of treatment, N = 203). None of the studied SNPs were significantly associated with LID susceptibility in the two samples. Therefore, we were unable to obtain proof of concept for our initial hypothesis of an overlapping contribution of genetic risk factors to TD and LID. Further studies in larger samples are required to reach definitive conclusions.
KeywordsTardive dyskinesia l-dopa induced dyskinesia Parkinson's disease Schizophrenia Genetics
- Boke O, Gunes S, Kara N et al (2007) Association of serotonin 2A receptor and lack of association of CYP1A2 gene polymorphism with tardive dyskinesia in a Turkish population. DNA Cell Biol 26:527–531Google Scholar
- Greenbaum L, Alkelai A, Zozulinsky P, Kohn Y, Lerer B (2012) Support for association of HSPG2 with tardive dyskinesia in Caucasian populations. Pharmacogenomics J 12:513–20Google Scholar
- Hely MA, Morris JG, Reid WG, Trafficante R et al (2005) Sydney Multicenter Study of Parkinson's disease: non-L-dopa-responsive problems dominate at 15 years. Mov Disord 20:190–199Google Scholar
- Kane JM (1995) Tardive dyskinesia: epidemiological and clinical presentation. In: Bloom FE, Kupfer DJ (eds) Psychopharmacology: the 4th generation of progress. Raven, New YorkGoogle Scholar