Pedigree charts are diagrams that show the genetic relationships within a family. They are commonly used in genetics to track the inheritance of traits or diseases. In a pedigree chart, squares represent males, circles represent females, and lines connecting them show the relationships between individuals. By analyzing pedigree charts, researchers can determine how traits are passed down through generations.
Here are some practice problems to help you understand how to interpret pedigree charts:
Pedigree Chart Practice Problems And Answers
1. In the following pedigree chart, what is the genotype of individual II-3? (Answers: II-3 is homozygous dominant for the trait)
2. In the pedigree chart below, what is the probability that individual III-6 is a carrier of the trait? (Answers: The probability is 50% that III-6 is a carrier)
Answers
1. II-3 is homozygous dominant for the trait because both of their parents are carriers, indicated by the shaded symbols in the pedigree chart.
2. The probability that III-6 is a carrier is 50% because one of their parents is affected by the trait, indicated by the filled-in symbol, and the other parent is a carrier, indicated by the half-filled symbol.