Club foot Club foot is a common congenital abnormality which

Club foot Club foot is a common congenital abnormality, which can be caused by both genetic and non-genetic factors. One family was studied where club foot was caused by an autosomal dominant allele (in the PITXl gene) with reduced penetrance. It was determined that 11 people in the family carried the mutation in PITXI, but only 8 of those people had club foot. What is the penetrance of the mutation in this family? 75% 73 % 25% 0 27% 100% 50%

Solution

Answer is 73%.

The penetrance of a disease-causing mutation is the proportion of individuals with the mutation who exhibit clinical symptoms. Here 8 out of 11 are showing the clinical symptoms. So it is 72.73%.