Question

Over a period of several years, a large hospital kept track of the number of births of babies displaying the trait achondroplasia. Achondroplasia is a very rare autosomal dominant condition resulting in dwarfism with abnormal body proportions. After 120,000 births, it was noted that there had been 27 babies born with achondroplasia. One physician was interested in determining how many of these dwarf babies result from new mutations and whether the apparent mutation rate in his area was higher than normal. He looked up the families of the 27 dwarf births and discovered that 4 of the dwarf babies had a dwarf parent. What is the apparent mutation rate of the achondroplasia gene in this population? Is it unusually high or low?

Answer 1

Answer:

In the population of the study, mutation in the achondroplasia gene is unusually high

Explanation:

In this population, the incidence of genetic mutation that leads to achondroplasia would be 6 children for every 30,000 births. In the general population, achodroplasia has an incidence of 1 per 30,000 births, which indicates that in this specific population, the mutation rate is high above average, which can be explained by a high prevalence of the gene in the population.

Achondroplasia is a genetic disease with inheritance of an autosomal dominant pattern and to suffer from the disease, only one copy of the defective gene is necessary.However, in recent years after several studies it has been possible to demonstrate that even achondroplasia could be generated even in new mutations in the germ cells of the parents.