"If you're a grandparent, a family health history is a gift you can give to your grandchildren," says James O'Leary of the nonprofit Genetic Alliance.

* Start with your own health and that of your parents, children and siblings. Then add grandparents, aunts, uncles and cousins from both sides of the family.

* Include a range of health conditions, from heart disease and cancer to arthritis and problems during pregnancies.

* Ask about the age when health problems arose or caused death.

* Ask follow-up questions, such as whether a heart attack was preceded by treatment for high blood pressure or high cholesterol.

* Include lifestyle information, such as family eating and exercise habits, where people live and common occupations.

* Keep information updated.

* Keep in mind that some relatives may not want to share their health history.