The incidence of cystic fibrosis in Caucasian populations.

Estimates of the newborn frequency of cystic fibrosis in different Caucasian groups 
range from 4 times more to 40 times less common than 
the generally accepted figure of 1:2000. Current meconium screening trials which 
may be effective in populations with the incidence equal to or 
greater than 1:2000, may be useful for populations with an incidence 
as low as 1:7000 only after maximum improvement of the methods. 
Once the true incidence or the variable incidence is proven for 
Caucasian populations, screening trails in Negro, Oriental and Indian populations will 
be required. 