Background: It has been suggested that genetic variation within candidate pharmacogenes contributes to
the differences in drug safety and efficacy as well as risk of adverse drug reactions among different ethnic groups.
Illustrating the polymorphic distribution of Very Important Pharmacogenes (VIPs) in various ethnic groups will
contribute to the development of personalized medicine for those populations.
Objective: The present study aimed to identify the polymorphic distribution of VIPs in the Circassian subpopulation
of Jordan and compare their allele frequencies with those of other populations.
Methods: A total of 130 healthy and unrelated Circassian adults from Jordan were randomly recruited and genotyped
for eleven VIP variants within the thiopurine S-methyltransferase (TPMT), ATP-binding cassette, sub-family B,
member 1 (ABCB1), and vitamin D receptor (VDR) genes via Sequenom’s MassARRAY® genotyping platform
Results: Our data on the allelic frequencies of the investigated VIP variants were compared to those of 18 other
populations, comprising 11 HapMap populations, 6 Exome Aggregation Consortium populations, and the Chechen-
Jordanian population from Jordan. Circassian-Jordanians were found to most resemble the African, Chechen-
Jordanian, European (Finnish), European (non-Finnish), and South-Asian populations.
Conclusion: Circassians from Jordan significantly differ from other populations in terms of the allelic frequencies of
selected VIP variants. The present findings constitute the first set of pharmacogenetic data for Circassian population
from Jordan, providing a basis for safe drug administration that may be useful in diagnosing and treating diseases in
this ethnic group.