Table 1.
Summary data on selected genetic polymorphisms of CYP2B6.
| CYP allele designationa | Key mutation(s)b rs number | Location, protein effect | Allele frequenciesc | Functional effect |
|---|---|---|---|---|
| CYP2B6*4 | g.18053(c.516) A>G rs2279343 | K262R (isolated) | 0.00 AA, Af 0.04 Ca 0.05–0.12 As |
↑ Expression, moderate substrate-dependent effects |
| CYP2B6*5 | g.25505(c.1459) C>T rs3211371 | R487C | 0.01–0.04AA, Af 0.09–0.12 Ca 0.05–0.12 Hs 0.01–0.04 As |
↓ Expression, in part compensated by ↑ specific activity |
| CYP2B6*6 | g.15631(c.516) G>T rs3745274 and g.18053(c.785)A>G rs2279343 | Q172H K262R |
0.33–0.5 AA, Af 0.10–0.21 As 0.14–0.27 Ca 0.62 PNG |
↓ Expression; ↓activity with efavirenz in vivo; some other substrates show ↑ activity |
| CYP2B6*18 | g.21011(c.983)T>C rs28399499 | I328T | 0.04–0.08 AA 0.05–0.12, Af 0.01 HS 0.00 As, Ca, PNG |
↓ Expression and activity |
| CYP2B6*22 | g.-82T>C rs34223104 |
promoter (TATA-box) | 0.00–0.025 AA, Af, As 0.024 Ca, Hs |
↑ Expression and activity ↑ Inducibility in vitro |
a
According to CYPallele nomenclature homepage http://www.cypalleles.ki.
b
Genomic (g.) and cDNA (c.) positions are given in bp.
c
Selected frequencies of individual ethnicities (AA, African American; Af African; As Asian; Ca Caucasian; Hs, Hispanic; PNG, Papua New Guineans) compiled from dbSNP http://www.ncbi.nlm.nih.gov/SNP and from the literature cited in the text.