The most common and most likely answer to this crossword clue is the 6 letter word INBRED
I've seen this crossword clue in Financial Times
I
N
B
R
E
D
More clues leading to the result INBRED
- Like some dynasties at home with money, so I’ve heard
- I notice colour associated with Indian native
- One new loaf, you might say is natural
- Said where yeast is lacking essential variety
- Bit of restlessness during sleeping is natural
- Native of fashionable Midlands city turning up shortly
- Where most are by midnight, assuming resistance is instinctive
- Popular food said to be from a limited gene pool
- Natural to be resting around 4, finally
- Home food, it’s said, is natural
Buddy explains!

The straight part
We know that "Natural" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case natural = inbred.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does INBRED mean?
INBRED noun- An inbred individual.
- Bred within; innate.
- Having an ancestry characterized by inbreeding.
- Describing a strain produced through successive generations of inbreeding resulting in a population of genetically identical individuals which are homozygous at all genetic loci.
- To breed or reproduce with those that are related.
- To breed with those that share common traits or qualities.
- To produce or generate within.