Is bipolar disorder have a higher incidence in a certain group of people?
for my biology project
It could.. It would depend because you never have total control over bipolar.
Bipolar disorder (or now referred to as Manic Depression) isn't totally genetic or only passed on through inheritance- so no.
It is true that bipolar disorder condition can have a higher incidence in a certain group of people. The people with a higher incidence are the under-diagnosis and misdiagnosis. Check out the link for more details http://health.nytimes.com/health/guides/disease/bipolar-disorder/print.html.