It’s peculiar, you conclude, to a certain kind of mice (7)
I believe the answer is:
endemic
'it's peculiar you' is the definition.
I can't judge whether this definition defines the answer.
'conclude to a certain kind of mice' is the wordplay.
I cannot quite understand how this works, but
'conclude' could be 'end' (I've seen this before) and 'end' is located in the answer.
an anagram of 'mice' is 'emic' which is within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for endemic that I've seen before include "(Of disease) widespread in an area" , "Native to (med.)" , "Peculiar to local area" , "(Of a disease) regularly found in a certain area" , "(Of a disease) prevalent in a group or area" .)