Skip to content
Use your HSA or FSA funds

Gene

CYP2B6

cytochrome P450 family 2 subfamily B member 6

Summary

Cytogenetic location
19q13.2
Coordinates
Chromosome 19: 40,991,282–41,018,398 (GRCh38)
Exons
9 exons across 27.1 kb
Protein
491 amino acids
Also known as
CPB6, CYPIIB6
Previous symbols
CYP2B
MANE Select transcript
ENST00000324071.10NM_000767.5
Locus type
gene with protein product
  • Very high
  • Confident
  • Low
  • Very low

Reference genomeGRCh38

Positions on gene and variant pages follow this choice, in this browser.

CYP2B6 and medicines

  • Efavirenz metabolism

    Pharmacogenomics

    CYP2B6 clears the HIV drug efavirenz. Reduced-function alleles raise blood levels, which is the main driver of the vivid dreams, dizziness and other central nervous system effects that lead people to stop the drug.

    • Relevant if you take efavirenz-based HIV therapy or nevirapine, and to a lesser degree sertraline, methadone or bupropion.

    Alleles the report reads

    • *18No function
    • *1Normal function
    • *9Decreased function
    • *6Decreased function

    Results CPIC describes

    • Poor Metabolizer
    • Indeterminate
    • Normal Metabolizer
    • Rapid Metabolizer
    • Ultrarapid Metabolizer
    • Intermediate Metabolizer
    MedicineCPIC levelGuideline
    efavirenzACYP2B6 and efavirenz
    sertralineBCYP2D6, CYP2C19, CYP2B6, SLC6A4, HTR2A and Serotonin Reuptake Inhibitor Antidepressants
    Show 3 more medicines
    MedicineCPIC levelGuideline
    bupropionB/C
    nevirapineB/C
    methadoneCCYP2B6 and methadone

    Calls *6 (516G>T with 785A>G), *9 (516G>T alone) and *18. Unphased, a 516G>T and 785A>G carried together are read as one *6 chromosome; rarer alleles are not assessed.

How CYP2B6 is laid out

  • Coding sequence
  • Untranslated region
  • Intron
  • Direction of transcription
  • Stretches short reads find hard
Chromosome 19, with a bracket where CYP2B6 sits. CYP2B6 and 31 genes near it on chromosome 19, from 40,504,840 to 41,504,839.Chromosome 1919q13.2p13.3p13.2p13.13p13.12p13.11p12p11q11q12q13.11q13.12q13.13q13.2q13.31q13.32q13.33q13.41q13.42q13.4340.6 Mb40.8 Mb41 Mb41.2 Mb41.4 MbSPTBN4: 40,466,241–40,576,464, forward strandSPTBN4SHKBP1: 40,576,844–40,591,399, forward strandSHKBP1LTBP4: 40,592,883–40,629,821, forward strandLTBP4NUMBL: 40,665,905–40,690,972, reverse strandNUMBLCOQ8B: 40,691,514–40,725,784, reverse strandCOQ8BITPKC: 40,716,964–40,740,860, forward strandITPKCACTMAP: 40,740,856–40,751,813, reverse strandSNRPA: 40,750,585–40,765,393, forward strandMIA: 40,768,997–40,777,490, forward strandMIAMIA-RAB4B: 40,771,648–40,796,943, forward strandRAB4B: 40,778,191–40,798,690, forward strandRAB4BRAB4B-EGLN2: 40,778,242–40,808,418, forward strandRAB4B-EGLN2EGLN2: 40,798,996–40,857,708, forward strandEGLN2: 40,801,297–40,898,282, forward strandCYP2A6: 40,841,915–40,850,493, reverse strandCYP2A6CYP2A7: 40,873,525–40,882,752, reverse strandCYP2A7CYP2B6: 40,991,282–41,018,398, forward strandCYP2B6CYP2A13: 41,088,451–41,096,195, forward strandCYP2A13CYP2F1: 41,114,432–41,128,381, forward strandCYP2F1CYP2S1: 41,192,911–41,207,540, forward strandCYP2S1AXL: 41,218,934–41,261,766, forward strandAXLHNRNPUL1: 41,262,496–41,307,787, forward strandHNRNPUL1TGFB1: 41,288,203–41,353,961, reverse strandTGFB1CCDC97: 41,310,149–41,334,014, forward strandCCDC97: 41,350,853–41,425,001, forward strandTMEM91: 41,350,885–41,384,742, forward strandTMEM91B9D2: 41,354,417–41,364,165, reverse strandB9D2EXOSC5: 41,367,173–41,397,441, reverse strandBCKDHA: 41,397,792–41,425,092, forward strandB3GNT8: 41,422,878–41,428,730, reverse strandDMAC2: 41,431,317–41,440,717, reverse strandDMAC2ERICH4: 41,443,152–41,444,765, forward strandDiagram of CYP2B6: 9 exons on the forward strand of chromosome 19Exon 1: 40,991,282–40,991,476, 195 basesExon 2: 41,004,001–41,004,163, 163 basesExon 3: 41,004,297–41,004,446, 150 basesExon 4: 41,006,905–41,007,065, 161 basesExon 5: 41,009,219–41,009,395, 177 basesExon 6: 41,009,994–41,010,135, 142 basesExon 7: 41,012,298–41,012,485, 188 basesExon 8: 41,012,674–41,012,815, 142 basesExon 9: 41,016,646–41,018,398, 1,753 bases1246895′3′

Exons of the gene's MANE Select transcript (release v1.5), from NCBI and EMBL-EBI, on the GRCh38 reference genome.

Chromosome bands from UCSC's GRCh38 ideogram (2022-10-29).

Nearby genes from Ensembl release 116, on GRCh38.

Exons make up 3.1 kb of the gene's 27.1 kb; 1,476 of those bases code for the protein.

Where this comes from

  • HGNC: the gene's symbol, name, other symbols and location.
  • MANE Select v1.5, from NCBI and EMBL-EBI: the transcript, its exons and coding sequence.
  • CPIC and PharmGKB: the alleles, results and medicines.

Cite this page

APA

Dante Labs. (n.d.). CYP2B6 gene: cytochrome P450 family 2 subfamily B member 6. Retrieved 16 October 2026, from https://dantelabs.com/genes/cyp2b6

Vancouver

Dante Labs. CYP2B6 gene: cytochrome P450 family 2 subfamily B member 6 [Internet]. [cited 16 October 2026]. Available from: https://dantelabs.com/genes/cyp2b6

One test. A lifetime of answers.

From $449Free shipping · Results in 6–8 weeks

Get my Genome Test