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Part 1: Creating a Pedigree File


A pedigree is a visual aid that is used to show the occurrence of a genetic disorder among members of a family. Symbols are used to represent unaffected males, unaffected females, affected males, and affected females in the family. The format is much like that of a typical family tree with lines connecting siblings to parents. The pedigree can span many generations.

The following legend shows the types of individuals that pedigree symbols represent:

  The following figure is an example of a pedigree. Individuals 1 and 2 are the parents, individuals 3-7 are their children.  



Numbers above each symbol represent the identification number of each member of the family.  Numbers below each symbol represent genetic markers for the disease.

Answer the following question correctly to continue.

Sorry, but your answer is incorrect.  Try again.

Which members in the pedigree above are males with the disorder? Check all appropriate boxes.

1 2 3 4 5 6 7