Wilder make-up unit? (4)

I believe the answer is:

gene

I believe this clue is a double definition.

'wilder' is the first definition.
(gene wilder)

'make-up unit?' is the second definition.
(dna)

(Other definitions for gene that I've seen before include "Vincent" , "Part of DNA" , "-- Pitney, singer" , "and 16 Down: Rockabilly singer" , "Unit of heredity significance" .)

I've seen this clue in The Guardian.

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