Medical history: How to compile your medical family tree
Your family medical history provides insight into the diseases and conditions that are common to your family. Use this history to give you clues about your risk of disease.
By Mayo Clinic staffYour family medical history — sometimes called a medical family tree or pedigree — is a record of illnesses and medical conditions affecting your family members. Similar to a family tree you might have drawn in school, a family medical history is a visual representation of the relationships among members of your family, but it also includes information for each person about diseases, age of disease onset, causes of death and other relevant health information.
How is a family medical history used?
You inherit half of your genetic profile from each parent. Along with the genetic information that determined your appearance, you inherited genes that may cause or increase your risk of certain medical conditions. Except for a relatively small number of genes, the identities of most disease-associated genes remain unknown.
A family medical history can serve as a "substitute" genetic test to help your doctor interpret the history of disease in your family and identify patterns that may be relevant to your own health. Your doctor and other health care professionals may use your family medical history to:
- Assess your risk of certain diseases
- Recommend changes in diet or other lifestyle habits that can lower disease risk
- Recommend treatments that can modify disease risk
- Determine what diagnostic tests to order
- Determine the type and frequency of appropriate disease screening tests
- Determine whether you or family members should get a specific genetic test
- Identify a condition that might not otherwise be considered by your doctor
- Identify other family members who are at risk of developing a certain disease
- Assess your risk of passing conditions on to your children
A family medical history can't predict your future health. With few exceptions, it only provides information about risk. Other factors — such as your diet, weight, exercise routine, other lifestyle habits, and exposure to pollutants or environmental factors — will also raise or lower your risk of developing certain diseases.
How do you gather information about your family's medical history?
Your family may want to work together on developing your family medical history. Therefore, holidays and reunions can provide a good opportunity for your relatives and you to gather information, fill in gaps in information, and talk to the "family historian," who may remember details about the health of deceased family members.
Not everyone, however, may be comfortable disclosing personal medical information. Be aware of a number of factors that may contribute to a person's reluctance to discuss medical issues:
- Feelings of shame regarding certain illnesses, such as alcoholism or mental illness
- Painful memories associated with a condition, such as multiple miscarriages
- Denial about the history of disease in the family
- Cultural or generational differences that influence feelings about health issues and personal privacy
- A lack of understanding of medical conditions
- Perceptions that a family medical history has no value
Consider the following strategies for addressing the issue with your relatives:
- Explain your purpose. Emphasize that your purpose is to create a record that will help you determine whether you and your relatives have a family history of certain diseases or health conditions. Offer to make the medical history available to other family members, so that they can share the information with their doctors.
- Provide several ways to answer questions. Some people may be more willing to share health information in a face-to-face conversation. Others may prefer answering your questions by phone, mail or e-mail.
- Word questions carefully. Don't start with personal questions. Begin your interview by asking questions about the whole family. When you begin discussing personal medical history, keep your questions short and to the point.
- Be a good listener. As your relatives talk about their health problems, let them speak without interruption. Listen without judgment or comment.
- Respect privacy. As you collect information about your relatives, respect their right to confidentiality. Some people may not want to share any health information with you. Or they may not want this information revealed to anyone other than you and your doctor.
What other sources of information may be beneficial?
You may want to consult other documents, such as existing family trees, baby books, old letters, obituaries or records from places of worship. Public records — birth certificates, marriage licenses and death certificates — are usually available in county record offices.
If you are adopted, ask your adoptive parents if they received any medical information about your biological parents at the time of your adoption. Adoption agencies may also have family medical information on file. If you were adopted through an open adoption process, you may be able to discuss your family's medical history directly with members of your biological family.
What information should you include in a family medical history?
Your goal is to gather as much accurate information as possible. Don't expect to find answers to all your questions, and don't worry if some details are missing.
If possible, your family medical history should include at least three generations. Compile information about your grandparents, parents, uncles and aunts, siblings, cousins, children, nieces and nephews, and grandchildren. For each person, gather the following information:
- Sex
- Date of birth
- For deceased relatives, age at the time of death and cause of death
- Diseases or other medical conditions
- Age of disease onset
- Diet, exercise habits, smoking habits or history of weight problems
Ask about the occurrence of the following diseases and medical conditions often associated with genetic risk:
- Cancer
- Heart disease
- Diabetes
- Asthma
- Arthritis
- Mental illness
- High blood pressure
- High cholesterol
- Stroke
- Kidney disease
- Alcoholism or other substance abuse
- Birth defects
- Vision loss
- Hearing loss
- Learning disabilities
- Mental retardation
- Miscarriages or stillbirths
Also include information about race and ethnicity because the risk of a particular disorder may be greater in one population group than in others.
How do you compile the information into a family tree?
Once you have gathered information about your family, create a medical family tree, or a diagram that visually depicts the relationships among family members. Record the medical information and other details about each person on your tree. If information about a disease or cause of death is unknown, don't guess at the answer. An incorrect guess can result in a poor interpretation of your medical history.
You can find samples of medical family trees and a list of commonly used symbols for pedigrees at the Web sites of the American Medical Association and the National Society of Genetic Counselors.
The office of the U.S. Surgeon General offers an electronic tool called My Family Health Portrait that provides a template for inputting information and generates a medical family tree for you. It is available in English and Spanish as an online tool or downloadable software.
What should you do with a completed family medical history?
Provide your doctor with a copy of your medical family history and ask him or her to review it with you. Your doctor may ask you questions for clarification and can help you interpret the relevance of certain patterns in your medical history. He or she may advise you immediately regarding preventive measures you can take or screening tests you should schedule.
Update your family medical history every couple of years and provide your doctor with a revised copy.
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Nov. 1, 2007
