How do researchers mark whether risk factors are present pedigree

A pedigree can be described as a diagram which is in the form of a tree and it  illustrates the ancestors of a family in a sequence. A pedigree lets researchers depict the carriers of a particular disease and the chances of transmission of a family disease in the next generation. Doctors can easily know about the risk factors related to family diseases by looking at the pedigree of a family.

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