Conversation so far:
in dear john what is wrong with the dad
In the 2010 film Dear John, Savannah mentions to John that his father may have a form of high-functioning autism known as Asperger's syndrome.
what are the characteristics of asperger's syndrome
Characteristics of Asperger syndrome include problems with social interactions and restricted and repetitive behavior.

Question: how many people are diagnosed
Self-contained rewrite: how many people are diagnosed with asperger syndrome