Pharmacogenetics Work to Advance Precision Medicine

Pharmacogenetics experts have created a standard terminology for reporting clinical pharmacogenetics test results to help improve medication safety and efficacy in precision medicine.

Published in Genetics in Medicine, researchers identified 14 terms used by medical testing laboratories and other professionals to describe the high-risk variations of the TPMT gene. Some of the terms included deficient function, no activity, homozygous deficient, and absent activity.

TPMT is a gene that encodes instructions for an enzyme to help break down the chemotherapy agents thiopurines. Any differences in TPMT’s DNA causes a small percentage of individuals to not be able to make a functional enzyme.

Experts used a consensus-building method that included several rounds of surveying to sift through the terms. More than 90% of the experts came to a consensus to refer to TPMT variations as poor metabolizer.

Terms were agreed upon to describe gene variations that affected function and used other standardized terminology to describe how the variations were likely to impact clinical care.

“Inconsistent terms can be confusing to clinicians, laboratory staff, and patients,” said senior study author James Hoffman, PharmD. “The lack of standard vocabulary has been a major obstacle to incorporating pharmacogenetics results in the patients’ electronic health record to help guide prescribing.”

As new information becomes available, and the specialty continues to grow, the terminology will be expanded upon and revised, noted first and corresponding study author Kelly Caudle, PharmD, PhD.

“We hope that establishing standard terminology will encourage more widespread inclusion of pharmacogenetics results in the electronic health records of patients to help realize the promise of precision medicine to individualize patient care,” Caudle said.