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Help! This question is about frequencies of alleles

One in 1700 Caucasian newborns in the U.S. have cystic fibrosis, a debilitating condition caused by the recessive c allele, where individuals with cystic fibrosis are cc. a) What is the frequency of the C and c allele in this population? b) What proportion of the population carries the allele for cystic fibrosis (that is, is heterozygous)? (FYI: Though homozygous recessive individuals are severely impaired by this condition, there appears to have been a selective advantage for heterozygous individuals in the past. The presence of one copy of the allele is thought to have protected bearers from serious diarrheal diseases, possibly cholera.)

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I do not actually know what I am doing. Does this look right to you?

q^2 = 1/1700 q = 0.02425
p = 1-q = 100 - 2.425 = .9757
2pq = 2 * .9757 * .02425 = 0.04733 (heterzygous)

http://www.nature.com/scitable/definition/hardy-weinberg-equation-299

My understanding may be too simple to help you with this homework. for example, if people with cystic fibrosis avoid having children, these equations do not apply.