Substrate dependent. Cytochrome P450 (P450) 2D6 is usually a big drug-metabolizing enzyme expressed in the liver1. CYP2D6 catalyzes the hepatic metabolism of a sizable number of clinically important drugs, like codeine, amitriptyline, fluvoxamine, risperidone, fluoxetine, aripiprazole, paroxetine, and dextromethorphan2,3. The CYP2D6 gene is hugely polymorphic. To date, more than 130 allelic variants have been designated by the Pharmacogene Variation Consortium (PharmVar)4,five.P2Y1 Receptor review Division of Pharmacogenomics and Personalized Medicine, Division of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand. 2Laboratory for Pharmacogenomics, Somdech Phra Debaratana Healthcare Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand. 3Advanced Research and Development Laboratory, Bumrungrad International Hospital, Bangkok, Thailand. 4Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children’s Mercy Kansas City, Kansas City, MO, USA. 5School of Medicine, University of Missouri-Kansas City, Kansas City, MO, USA. 6Unit of PharmacoTherapy, -Epidemiology and -Economics, ROCK2 Purity & Documentation Groningen Study Institute of Pharmacy, University of Groningen, Groningen, The Netherlands. 7Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Health-related Center Groningen, Groningen, The Netherlands. 8Yuwaprasart Waithayopathum Kid and Adolescent Psychiatric Hospital, Division of Mental Well being Solutions, Ministry of Public Well being, Samut Prakan, Thailand. e mail: [email protected] Reports | (2021) 11:4158 | https://doi.org/10.1038/s41598-021-83570-w 1 Vol.:(0123456789)www.nature.com/scientificreports/CYP2D6 allele frequencies differ substantially amongst various ethnic and ancestral populations6. The decreased function CYP2D610 allele (100C T, P34S) is definitely the most common allele in East Asian populations, including Thai, Chinese, Taiwanese, Korean, Vietnamese, and Filipino106. This allele is also observed in other populations, such as Europeans, Africans, and their descendants, its frequency, nevertheless, considerably lower8. Conversely, the nonfunctional CYP2D64 allele is additional frequent in European populations but is rarely observed in Asian populations8. CYP2D6 genetic variation leads to a wide range of metabolic capacity ranging from no to elevated activity. Determined by their genotype, men and women are grouped into four phenotype groups, i.e., poor metabolizers (PMs), intermediate metabolizers (IMs), regular metabolizers (NMs), and ultrarapid metabolizers (UMs)17. The activity score system (AS) has been broadly accepted to translate the CYP2D6 genotype into phenotype and the Clinical Pharmacogenetics Implementation Consortium (CPIC) as well as the Dutch Pharmacogenetics Functioning Group (DPWG) for their respective guidelines18,19. Briefly, every allele is assigned a value of 0, 0.5 or 1 reflecting no function, decreased or normal function, plus the sum of the values supplies the AS of a genotype. The preceding CPIC translation method classified AS = 0 as PM, AS = 0.5 as IM, AS = 1 to two as NM, and two as UM. In an effort to harmonize genotype to phenotype translation, a CPIC-led functioning group has recently published a revised process and recommends making use of this new process to translate genotype to phenotype19. A single main change was downgrading the worth utilized for activity score calculation of the decreased function CYP2D610 allele from 0.five to 0.25 to much more accurately reflect the drastically decreased f.