Fundamental racial problem with daughter (7)
I believe the answer is:
radical
'fundamental' is the definition.
(I've seen this before)
'racial problem with daughter' is the wordplay.
'problem with' is an anagram indicator.
'daughter' becomes 'd' (genealogical abbreviation).
'racial' mixed up with 'd' makes 'RADICAL'.
(Other definitions for radical that I've seen before include "Political extremist" , "Dial car in order to be drastic" , "left-winger" , "Fundamental - thoroughgoing" , "Tending towards extreme political views" .)