Achondroplasia Is a Form of Dwarfism That Is Inherited in Humans

question 92

Multiple Choice

Achondroplasia is a form of dwarfism that is inherited in humans as an autosomal dominant disorder. A survey in a small country showed that, within a two-year period, there were 12 children with normal parents born with this disorder out of a total of 420,000 births. What is the mutation rate in mutations/locus/generation?

• A) 1.4 × 10^-5
• B) 2.8 × 10^-6
• C) 2.5 × 10^-5
• D) 2.8 × 10^-5
• E) 7.4 × 10^-6