Low-frequency and rare genetic variants may play a role in the development of tardive dyskinesia (TD), suggests a preliminary study published in European Neuropsychopharmacology.
“Tardive dyskinesia occurrence is influenced by both clinical and demographic variables, as well as genetic factors,” wrote researchers. “Contribution of common variants to tardive dyskinesia susceptibility has been investigated in recent years, including by the genome-wide association study approach, but results are inconsistent.”
In an attempt to examine the involvement of low-frequency and rare variants in the phenotype, this study used whole exome sequencing on 38 patients. Participants included 20 Ashkenazi Jewish patients with schizophrenia and severe TD and 18 patients who did not have TD despite having taken antipsychotic medications for more than a decade.
“We were able to identify several interesting rare (1%-5%) and extremely rare (<1%) loss-of-function variants, which are possibly related to tardive dyskinesia susceptibility and are biologically plausible,” researchers reported. “[A] follow-up case-control association study in a larger Jewish tardive dyskinesia sample is needed to confirm these results.”
The study also identified extremely rare patient-private mutations in participants with severe tardive dyskinesia. Such variants, researchers wrote, looked to be enriched in numerous neuropharmacologic pathways involved in tardive dyskinesia.