Question

The Amish are a group of people who live in America. This group was founded by 30 Swiss people, who moved to America many years ago. The Amish do not usually marry people from outside their own group.

One of the 30 Swiss founders had a genetic disorder called Ellis-van Creveld syndrome. People with this disorder have heart defects, are short and have extra fingers and toes. Ellis-van Creveld syndrome is caused by a faulty allele.

In America today, about 1 in 200 Amish people are born with Ellis-van Creveld syndrome. This disorder is very rare in people in America who are not Amish.

Use the information provided and your knowledge of the founder effect to explain why Ellis-van Creveld syndrome occurs at a higher frequency in the Amish population than in people in America who are not Amish.

Answer 1

The higher prevalence of Ellis-van Creveld syndrome in the Amish population is attributed to the founder effect, where one of the small group of original founders carried a recessive allele for the disorder.

Step-by-step explanation:

The higher frequency of Ellis-van Creveld syndrome in the Amish population compared to the general American population can be explained by the founder effect. The founder effect occurs when a new population is established by a small number of individuals, resulting in a limited genetic variation and an increased presence of specific genetic traits. In the case of the Amish, one of the original 200 founders carried a recessive allele for Ellis-van Creveld syndrome. With limited numbers and low rates of marriage outside their community, this allele became more common among the Amish than in the broader population.

The Amish community in the U.S. grew from approximately 200 Swiss and German founders in the mid-1700s. These founders carried particular gene mutations, such as that for Ellis-van Creveld syndrome. Due to the Amish's lifestyle of living in small rural communities and rare intermarrying with outsiders, the frequency of this genetic disorder increased significantly within the population.