African region not found in Gabon at all? Yes and no (5)
I believe the answer is:
natal
'african region not found in gabon' is the definition.
I can't tell whether this defines the answer.
'at all? yes and no' is the wordplay.
'all? yes' becomes 'al' (I can't explain this - if you can you should give a lot more credence to this answer).
'and' is a charade indicator (letters next to each other).
'no' becomes 'n' (common abbreviation).
'at'+'al'='atal'
'atal' after 'n' is 'NATAL'.
Can you help me to learn more?
(Other definitions for natal that I've seen before include "description of delivery" , "Relating to birth or the buttocks" , "South African place" , "former SA province" , "Relating to birth - former South African province" .)