title: Influence of environmental and genetic factors on CYP1A2 activity in individuals of South Asian and European ancestry.
abstract: The drug-metabolizing enzyme CYP1A2 contributes to the metabolism of a number of commonly used medicines and displays wide interindividual variability. The aim of this study was to investigate CYP1A2 activity in a population of South Asian ancestry and compare it with a population of European ancestry. CYP1A2 activity was determined using the 4 h paraxanthine/caffeine saliva concentration ratio following a 100-mg oral dose of caffeine in healthy individuals of South Asian (n = 166) and European (n = 166) ancestry. Participants were surveyed for extrinsic ethnic factors and genotyped for polymorphisms in CYP1A2 and related genes. Significantly lower CYP1A2 activity was observed in South Asian participants (median: 0.42; range: 0.10-1.06) as compared with European participants (0.54; 0.12-1.64) (P < 0.01). Multiple linear regression indicated that 41% of the variability in CYP1A2 activity could be explained by the diet, lifestyle, and genetic factors studied.
authors.affiliation: Faculty of Pharmacy, The University of Sydney, Sydney, Australia.
authors.forename: V
authors.initials: V
authors.lastname: Perera
authors.forename: A S
authors.initials: AS
authors.lastname: Gross
authors.forename: A J
authors.initials: AJ
authors.lastname: McLachlan
mesh_terms: D000293:Adolescent; D000328:Adult; D001211:Asia, Western / Q000208:ethnology; D044466:Asian People / Q000208:ethnology / Q000235:genetics*; D001315:Australia / Q000208:ethnology; D003430:Cross-Sectional Studies; D019388:Cytochrome P-450 CYP1A2 / Q000235:genetics* / Q000378:metabolism; D004777:Environment; D004789:Enzyme Activation / Q000502:physiology; D005260:Female; D006801:Humans; D007194:India / Q000208:ethnology; D008019:Life Style / Q000208:ethnology; D008297:Male; D011446:Prospective Studies; D013188:Sri Lanka / Q000208:ethnology; D044465:White People / Q000208:ethnology / Q000235:genetics*; D055815:Young Adult
chemical_list: C504573:CYP1A2 protein, human; D019388:Cytochrome P-450 CYP1A2