5. Cystic fibrosis is a genetic disease that affects the lungs and other organs. Affected individuals are prone to infection because they can't produce normal mucous that helps the lungs clear bacteria. People with the disease have two mutant copies of the cystic fibrosis gene (CFTR), while people with a single mutant copy (heterozygous) of CFTR don't have the disease but are carriers. a. What is the mode of inheritance (dominant or recessive) of cystic fibrosis? b. If the mutant allele that causes cystic fibrosis is present at an allele frequency of 1 in 50 (0.02), what proportion of people have the disease?
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We know that cystic fibrosis is a genetic disease caused by having two mutant copies of the CFTR gene. This means that the disease is inherited in a recessive manner, as having only one mutant copy (heterozygous) does not cause the disease. Show more…
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Cystic fibrosis is a genetic disorder. It is a recessive trait that is determined by two alleles. Suppose two parents each carry at least one recessive allele, but neither of them has cystic fibrosis. Which statement reflects the likelihood of a child of these parents having cystic fibrosis? The child cannot have the disease because only the dominant alleles will be passed on. The child will have the disease because only recessive alleles will be passed on. The child may or may not have the disease because a recessive gene from each parent may be passed on. The child may or may not have the disease because the disease does not depend on the alleles of the parents.
Sri K.
Cystic fibrosis (CF) is caused by a genetic mutation resulting in defective proteins in secretory cells, mainly in the epithelial lining of the respiratory tract. The one in every 2,000 Caucasian babies who has the disease is homozygous for the recessive mutant. Although medical treatment is becoming more effective, in the past, most children with CF died before their teens. About 20 Caucasian in 2,000 are carriers of the trait, having one mutant and one normal allele, but they do not develop the disease. According to rules of population genetics, the frequency of the homozygous recessive genotype should be rarer than it is. What is one possible explanation for the unusually high frequency of this allele in Caucasian population?
Emilee F.
Cystic Fibrosis (CF) is a disease caused by a mutation in a specific gene. Since one "good" copy of the gene produces enough protein, the disease is recessive. CF only shows up when both copies of the gene have the mutation. Suppose that a man with a family history of CF marries a woman with no history of the disease. The woman has no genes for CF (homozygous dominant), while the man is a carrier (heterozygous) and does not have the disease. If these people become parents, a) what are the chances that their children will have CF? b) What are the chances that the children will be carriers? Display your answer in percentages for each question, like this: % ; % Or like this: % and %
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