DNA unit (4)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dna unit</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for gene that I've seen before include "affects someone's make-up" , "Element of heredity" , "___ Kelly, star of Singin' In The Rain, d. 1996" , "Hereditary determinant" , "Bodily factor controlling heredity" .)
(Other definitions for strand that I've seen before include "Bit of wire, say" , "that may be found by the sea" , "string" , "Yarn - thread" , "Shore; single fibre" .)