Cystic Fibrosis is affected by only one gene and because of this it is inherited by a process called monohybrid inheritance. This simply means that only one gene is involved.
Cystic Fibrosis is a recessive condition, which means only if an individual is homozygous for for the disorder they will show it.
If an individual is heterozygous and has the condition then they are a carrier of cystic fibrosis.
Links:
Genomics Website
CF website
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