Hi,

I am not a maths guy, and am working on an article for a narcolepsy support group.

The problem is this:

The number of people in the general population who suffer from narcolepsy is estimated to be 1 in 2000

90% of people who have narcolepsy have the HLA-DQB1*0602 genetic marker.

25% of the population have the HLA-DQB1*0602 genetic marker.

So it seems logical to say that the number of people in the population who have HLA-DQB1*0602 genetic marker who have narcolepsy would be 1 in 500 Is that correct?

And what would be the number of people in the population who do not have the HLA-DQB1*0602 genetic marker who have narcolepsy?

Thanks in a advance,

Philip