I need to know the genes of the parents?

Question

I need to know the genes of the parents?
There are 4 children, 2 boys 2 girls. 2 boys and one girl has cystic fibrosis. Both parents and the other girl appear to be healthy. Using C as dominant(No Cystic Fibrosis) and c as recessive(Cystic fibrosis) What are borth of the aprents. Are they CC, Cc.

Answer 1

you need to speak to a genetics counselor usually located at a medical university hospital
then you would need a family history, then finally a sanple of tissue for the dna to be read of each but thats not needed once a genetics counsel takes place

Answer 2

They are
Cc, Cc

the punnent square:
..........C........c

C.......CC.....Cc

c .......Cc....[cc]