Club foot is a rare disease due to congenital skeletal abnormalities, both genetic and nongenetic factors are thought to be responsible for club foot. A family in which club foot was inherited as an autosomal dominant trait with reduced penetrance was identified in 2008. It was found that a mutation in the PITXI gene that caused club foot in this family. Through DNA testing, they determined that 11 people in the family carried the PITXI mutation, but only 8 of these people had club foot. Required:
What is the penetrance of the PIXTI mutation in this family?

72.72%

Explanation:

The Penetrance of the PIXTI mutation in this family can be represented as

The Penetrance represents the percentage of people who show/have the disease

family size = 11

number of people with the disease = 8

Penetrance of PIXTI in the family can be calculated as  = 8/11 * 100

                   = 0.7272  * 100

                   = 72.72%

The remaining 27.38 % are just carriers of the PITXI gene

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.