Autry or Kelly (4)
I believe the answer is:
gene
I believe this clue is a double definition.
'autry' is the first definition.
(I've seen this in another clue)
'kelly' is the second definition.
(I've seen this in other clues)
(Other definitions for gene that I've seen before include "Part of chromosome" , "Basic unit of heredity" , "DNA unit" , "Bodily factor controlling heredity" , "Hereditary DNA sequence" .)