Dopamine DRD2 polymorphism (DRD2/ANNK1-Taq1A) is not a significant risk factor in writer’s cramp

Abstract

Writers’ cramp is a movement disorder with dystonic co-contraction of fingers and hand during writing and is part of the clinical spectrum of focal dystonias. Previous studies showed reduced striatal dopamine receptor D2 (DRD2) availability in dystonia. The expression of D2 receptors is modulated by a DRD2/ANKK1-Taq1A polymorphism (rs1800497). This study addresses the question of whether the DRD2/ANKK1-Taq1A polymorphism is a risk factor for writer’s cramp. We determined the DRD2/ANKK1-Taq1A polymorphism 34 patients with writer’s cramp compared to 67 age matched controls. 35.3% of the patients and 31.3% of our controls were assigned to the A1 genotype status (p = .7). Therefore DRD2/ANKK1-Taq1A gene is not a significant risk factor in the evolution of writer’s cramp.

Keywords:

• Basal ganglia
• DRD2/ANNK1-Taq1A
• genetics
• task specific dystonia
• Writer’s cramp

Acknowledgements

We are indebted to the patients and normal volunteers for participating in this study. The authors declare that there are no conflicts of interest.

Disclosures

All authors report no conflicts of interest directly related to the present study. Kirsten E. Zeuner reports grants form German Research Foundation, the Benign Essential Blepharospasmus Foundation, Allergan, and an unrestricted grant from Ipsen. Karsten Witt reports grants from German Research Council and the German Ministry of Education and Health.