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Know your family history

How to start compiling your medical family tree

Begin your medical family tree by making a list of your blood relatives, both living and deceased:

  • First-degree relatives: your parents, siblings, and children
  • Second-degree relatives: your grandparents, aunts, uncles, nieces, nephews, and half-siblings
  • Third-degree relatives (if known): great-grandparents, first cousins, great-aunts and great-uncles

Jot down approximate birth dates and death dates wherever you can. Do not include people who are related to you by marriage or adoption.

Don't worry if there are gaps in your family tree. It's common not to know much about second- and third-degree relatives. Your parents or siblings may be able to supply some of the missing information when you speak to them.