Polymorphisms in the CYP1A2 gene and theophylline metabolism in patients with asthma.

Article Details


Obase Y, Shimoda T, Kawano T, Saeki S, Tomari SY, Mitsuta-Izaki K, Matsuse H, Kinoshita M, Kohno S

Polymorphisms in the CYP1A2 gene and theophylline metabolism in patients with asthma.

Clin Pharmacol Ther. 2003 May;73(5):468-74.

PubMed ID
12732846 [ View in PubMed

BACKGROUND: Cytochrome p450 (CYP) 1A2 gene polymorphisms are thought to be involved in theophylline metabolism. OBJECTIVE: We analyzed the effect of genetic polymorphisms in the 5'-flanking region to the first intron of the CYP1A2 gene on theophylline metabolism in 75 Japanese patients with asthma and 159 healthy Japanese volunteers. METHODS: Genetic polymorphisms were detected at 4 sites of the CYP1A2 gene, -2964(G/A) and -1569(T/del) in the 5'-flanking region and 155(T/G) and 731(A/C) in the first intron. RESULTS: There were no significant differences in the distribution of gene polymorphisms between the asthmatic and control groups. Among asthmatic patients, theophylline clearance was significantly lower in patients with the polymorphism at site -2964(G/A) whose genotype was G/A (0.029 +/- 0.001 L x h(-1) x kg(-1)) or A/A (0.029 +/- 0.002 L x h(-1) x kg(-1)) than in those whose genotype was G/G (0.034 +/- 0.001 L x h(-1) x kg(-1)) (P <.01 and P <.05, respectively). High theophylline clearance levels significantly correlated with age in the G/G subgroup of site -2964(G/A) (P <.05, r = -0.35) but not in the G/A or A/A subgroup. CONCLUSION: Given its potential side effects, theophylline may need to be used with care in patients with the A allele at site -2964(G/A) in the CYP1A2 gene, because theophylline metabolism levels are lower in such patients, particularly in young asthmatic individuals.

DrugBank Data that Cites this Article

DrugInteracting Gene/EnzymeAllele nameGenotypesDefining change(s)Type(s)DescriptionDetails
TheophyllineCytochrome P450 1A2
Gene symbol: CYP1A2
UniProt: P05177
-2964(G/A)(A;A) / (G;A)
  • A Allele
Effect Directly StudiedPatients with this genotype have reduced metabolism of theophylline.Details