The entire list is available on GENDER_IDNT_DTL table.
*SCC_GENDER_ID - Gender Ident
FIELD
VALUE DESCR
AG Agender
DG Demigender
GF Genderfluid
GQ Genderqueer
MA Man
NB Nonbinary
NT Not in list
PN Prefer not to say
TG Transgender
TM Trans Man
TN Trans Woman
TS Two-spirit
US Unspecified
WO Woman