Info, ultimately instructive, which parent passes to child (4)
I believe the answer is:
gene
'info ultimately instructive which parent passes to child' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'info ultimately instructive' is the wordplay.
'info' becomes 'gen' (informal term for information).
'ultimately' says to take the final letters.
The final letter of 'instructive' is 'e'.
'gen'+'e'='GENE'
Can you help me to learn more?
(Other definitions for gene that I've seen before include "DNA unit" , "Unit of heredity significance" , "affects someone's make-up" , "Something got from parent < for boy" , "and 16 Down: Rockabilly singer" .)