BCyrius: An Upgraded Version of Cyrius for Accurate CYP2D6 Genotyping From Short-Read Sequencing Data

Pharmacogenomics is a field of personalized medicine that aims to tailor drug dosing based on the genetics of an individual. The polymorphic and complex CYP2D6 gene is important to analyze because of its role in the metabolism of approximately a quarter of all drugs. Several bioinformatic tools have been developed to genotype CYP2D6 from short-read sequencing data. Among these, Cyrius, a tool specifically designed for CYP2D6 genotyping, has demonstrated high performance across various datasets. However, Cyrius has not been updated in the past 3 years, during which dozens of new star alleles have been identified and some previously defined ones revised. In this work, we simulated all known CYP2D6 haplotypes to assess the ability of Cyrius to identify them. In that dataset, Cyrius was unable to call or misidentified 50 of 360 samples. Given the importance of providing an up-to-date tool, particularly in clinical settings, we present an upgraded version of the tool, named BCyrius, which includes all the missing star alleles as well as revisions to the previously listed ones. BCyrius successfully identified 100% of the currently defined minor star alleles, higher than Cyrius (85.6%) and the two other tested tools, Aldy and StellarPGx, which identified 92.2% and 87.8%, respectively. BCyrius also demonstrated slightly improved performance on a dataset of real biological samples, resulting in a higher call rate while maintaining similar accuracy with Cyrius. In addition to providing genotyping results, BCyrius also reports the predicted phenotype, along with information for each detected haplotype, including population frequencies.