Inherited Disorders (GCSE Biology)

A scientist finds a new inherited disorder in a family and wants to show the disorder is caused by a single gene mutation. Which evidence would best support a single-gene inheritance pattern?

A pedigree chart shows a child with a dominant inherited disorder born to two parents, one affected and one unaffected. What is the most likely genotype of the affected parent?

Cystic fibrosis (CF) is caused by a faulty CFTR gene and is inherited as a recessive trait. If two carrier parents (both heterozygous) have a child, what is the probability the child will have CF?

Which scenario is an example of natural selection acting on genetic variation in a population?

In a Punnett square cross between two heterozygous parents (Aa × Aa) for a recessive disorder, what proportion of their children will be carriers (heterozygous)?

A new drug is being developed to treat a genetic disease. Which step must occur before the drug is widely prescribed to patients?

Which term describes a person who carries a recessive disease allele but does not show the disease symptoms?

In pedigree analysis, a disease that appears in every generation and affects both sexes equally is most likely to be inherited how?

Polydactyly (extra fingers or toes) is caused by a dominant allele. Which genotype would result in a person showing the polydactyly trait?

What is the role of genetic counselling when a family has a known inherited disorder?

Sickle cell disease is caused by a recessive allele. Heterozygous individuals (carriers) have some resistance to malaria. What evolutionary concept explains why the sickle cell allele remains in some populations?