One of the most important tools used by genetic professionals is the pedigree, a pictorial description of a family tree. A complete pedigree provides information about the biological relationships of individuals in the family, their medical history, the pattern of inheritance of a genetic disorder in the family, variable expression of the disorder, which family members are at risk, fertility of individuals (including pregnancies, miscarriages, and stillbirths), and family members who are dead. Physicians sometimes refer to a pedigree as a "genogram." However, genograms usually contain more social information about family relationships than a traditional pedigree used by geneticists and genetic counselors. For example, a genogram can show a teenage child who has a poor relationship with a parent or an individual estranged from the family.

Pedigree symbols used to indicate familial relationships.

Use of Pedigrees

Pedigrees can be used in the clinical setting, such as genetic counseling...