Cystic Fibrosis Genetics Concepts

The video tutorial explains autosomal recessive inheritance using cystic fibrosis as an example. It describes how recessive genes on autosomes affect phenotypes and genotypes, using genetic combinations of parents to predict offspring outcomes. The tutorial also covers the probability of inheriting cystic fibrosis and the implications for genetic counseling, emphasizing the classic monohybrid 3:1 ratio in genetic inheritance.

What is an example of a condition that follows autosomal recessive inheritance?

• Sickle cell anemia

• Color blindness

• Hemophilia

• Cystic fibrosis

In the context of cystic fibrosis, what does a capital 'C' represent?

• A mutated gene

• A recessive gene

• A dominant gene

• A carrier gene

If both parents are carriers of the cystic fibrosis gene, what is their genotype?

• Cc

• cC

• cc

• CC

What is the probability that a child will be a carrier if both parents are carriers of the cystic fibrosis gene?

• 100%

• 25%

• 75%

• 50%

What is the genotype of a child who is affected by cystic fibrosis?

• CC

• Cc

• cC

• cc

What is the classic monohybrid ratio observed in autosomal recessive inheritance?

• 4:1

• 1:1

• 3:1

• 2:1

What is the chance that a child will be perfectly normal and not a carrier if both parents are carriers?

• 25%

• 50%

• 75%

• 100%

What is the probability that a child will suffer from cystic fibrosis if both parents are carriers?

• 10%

• 25%

• 50%

• 75%

What does it mean if a person is phenotypically normal but genotypically heterozygous for cystic fibrosis?

• They are a carrier

• They are affected by the disease

• They have two dominant genes

• They have two recessive genes

What is the implication for future generations if a child is a carrier of the cystic fibrosis gene?

• They will not be affected by the gene

• They may pass the gene to their children

• They cannot pass the gene to their children

• They will definitely have the disease