The cytochrome P 450 phase I enzymes involved in the conversion of tamoxifen to the N-desmethyl-tamoxifen (DMT) metabolite are listed (rat and human) with aliases in parentheses, full names and links to gene report pages:

Rat
Cyp3a2 – cytochrome P450, family 3, subfamily a, polypeptide 2
Cyp3a23/3a1 (Cup3a1, CUPIIIA1), cytochrome P450, family 3, subfamily a, polypeptide 23/polypeptide 1

Human (the main contributing enzymes in bold)
CYP3A4 (CYP3A, CYPIIIA3, CYPIIIA4) – cytochrome P450 family 3 subfamily A member 4
CYP3A5 (CYP35, CYPIIIA5) – cytochrome P450 family 3 subfamily A member 5
CYP2D6 (CYPD6, VYPIID6) – cytochrome P450 family 2 subfamily D member 6
CYP1A1 (CYP1, CYPIA1) – cytochrome P450 family 1 subfamily A member 1
CYP1A2 (CYP12, CYPIA2) – cytochrome P450 family 1 subfamily A member 2
CYP2C8 (CYPIIC8, CPC8) – cytochrome P450 family 2 subfamily C member 8
CYP2C9 (CPC, CYPIIC9, P450IIC9) – cytochrome P450 family 2 subfamily C member 9
CYP2C19 (CYPIIC17, CYPIIC19) – cytochrome P450 family 2 subfamily C member 19