PI-032 - THE FREQUENCY OF SLCO1B1*5 IN WOMEN OF ASIAN, NATIVE HAWAIIAN, AND PACIFIC ISLANDERS SUBGROUPS: STEPS TO INCREASE RACIAL DIVERSITY IN PHARMACOGENETIC RESEARCH.

K. Alrajeh, Y. Roman; Virginia Commonwealth University, Richmond, VA, USA.

Background: The solute carrier organic anion 1B1 (SLCO1B1) gene encodes for the organic anion transporter protein (OATP1B1) that is involved in the active cellular influx of many endogenous and xenobiotic compounds. SLCO1B1*5 (rs4149056 T>C) is a well-established clinically actionable pharmacogenetic variant. The frequency of SLCO1B1*5 is lacking in specific population subgroups. The study aims to assess the frequencies of SLCO1B1*5 in Asian, Native Hawaiian, and Pacific Islander (NHPI) subgroups compared to European (EUR).

Methods: A cross-sectional study using biobanked DNA of individuals with a complete descent of self-identified Filipino, Korean, Japanese, Native Hawaiian, Marshallese, and Samoan. The University of Hawaii Biorepository provided de-identified DNA samples of 1064 post-partum women aged 18 years or older. The Ensembl genome browser was used to compare the frequencies of SLCO1B1*5 in population subgroups compared with EUR. Chi-square or Fisher’s exact test was used when appropriate with p< 0.007 for statistical significance.

Results: The overall genotype call rate of SLCO1B1*5 was 97%. In each population subgroup, the frequency of the SLCO1B1*5 variant was significantly lower (4-12%) than EUR (15%). The frequencies of the SLCO1B1 decreased function (7-14%) and no function (0-0.5%) phenotypes were significantly lower in our population subgroups than EUR (26% and 3%, respectively). Relative to our population subgroups, Filipino and Korean subgroups had the highest frequency of SLCO1B1*5.

Conclusion: This is the first report on the frequencies of SLCO1B1*5 in women of Asian and NHPI descent with distinct population subgroup differences. Differential allele frequency of SLCO1B1 among population subgroups underscores the importance of increasing racial and ethnic diversity in pharmacogenetic research.