4β-hydroxycholesterol is a new endogenous CYP3A marker: relationship to CYP3A5 genotype, quinine 3-hydroxylation and sex in Koreans, Swedes and Tanzanians

U Diczfalusy, J Miura, HK Roh… - Pharmacogenetics …, 2008 - journals.lww.com
Objectives To study the potential endogenous marker of CYP3A activity, 4β-
hydroxycholesterol, and its relation to sex and the CYP3A5 geno/haplotypes and compare
with CYP3A4/5 catalyzed 3-hydroxylation of quinine in the three major races. Methods The
plasma concentration of 4β-hydroxycholesterol was measured in healthy Tanzanians (n=
138), Swedes (n= 161) and Koreans (n= 149) by gas chromatography–mass spectrometry.
The metabolic ratio of quinine/3-hydroxyquinine in plasma 16-h post dose was determined …