NEET BIOLOGY

Detailed explanation-1: -An individual must inherit two non-functioning CF genes – one from each parent – to have CF. If both parents are carriers there is a 1 in 4 (25 percent) chance that both will pass on the non-functioning gene, which would result in a pregnancy affected with cystic fibrosis.

Detailed explanation-2: -If both parents, are carriers for CF, a future child could get two mutations, (C) one from each parent and therefore have cystic fibrosis. When both parents are carriers (CN), every baby has 25% chance of having cystic fibrosis.

Detailed explanation-3: -Each time two CF carriers have a child, the chances are: 25 percent (1 in 4) the child will have CF.

Detailed explanation-4: -25 percent (1 in 4) the child will have CF. 50 percent (1 in 2) the child will be a carrier but will not have CF. 25 percent (1 in 4) the child will not be a carrier of the gene and will not have CF.

Detailed explanation-5: -Frequency. Cystic fibrosis is a common genetic disease within the white population in the United States. The disease occurs in 1 in 2, 500 to 3, 500 white newborns. Cystic fibrosis is less common in other ethnic groups, affecting about 1 in 17, 000 African Americans and 1 in 31, 000 Asian Americans.