(a(i))[2]
Explain briefly how two parents who do not have CF may have a child with CF.
(a(ii))[2]
Describe two separate ways that CF affects the lungs.
(b(i))[2]
Outline, with reference to CF, what gene therapy means.
(b(ii))[2]
Describe one potential advantage and one potential disadvantage of using gene therapy to treat CF.