Which statement about cystic fibrosis is true?(1 point)

Question

Responses

Cystic fibrosis is caused by a mutation in which a dominant allele replaces a recessive allele.
Cystic fibrosis is caused by a mutation in which a dominant allele replaces a recessive allele.

Cystic fibrosis affects a person's ability to make normal red blood cells.
Cystic fibrosis affects a person's ability to make normal red blood cells.

Cystic fibrosis is caused by a deletion of one codon in the DNA molecule.
Cystic fibrosis is caused by a deletion of one codon in the DNA molecule.

Carriers have an advantage over people who do not have the cystic fibrosis mutation.

Answer 1

The correct statement about cystic fibrosis is:

Carriers have an advantage over people who do not have the cystic fibrosis mutation.

This is because carriers of one copy of the cystic fibrosis gene mutation (CFTR) may have some protection against certain diseases, such as cholera or typhoid fever, due to the altered ion transport mechanisms affecting their intestinal and respiratory systems. The other statements provided are inaccurate regarding the cause and effects of cystic fibrosis. Specifically, cystic fibrosis is inherited in an autosomal recessive pattern, is related to a mutation in the CFTR gene, and involves the deletion of three nucleotides (not just one codon) that leads to the loss of a phenylalanine residue in the protein.