Relating to heredity (7)
I believe the answer is:
genetic
'relating to heredity' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for genetic that I've seen before include "Like type of code" , "Relating to heredity" , "regarding family sources" , "handed down through the generations" , "Tending to occur among members of a family usually by heredity" .)