Family trees

By Chaya Murali, MS4

It’s a standard part of the medical interview: family history. “Do you have a family history of cancer?” we ask our patients. “Heart disease? Diabetes?” We modify it depending on what rotation we’re on. For our pregnant patients, we ask if anyone in her family has given birth prematurely or had difficulties in pregnancy. On pediatrics, we ask about developmental delays or unexplained deaths in childhood. But in no field does the family history take on as important a role as in clinical genetics.

I’ve been interested in clinical genetics since I was 18 years old, and at Baylor College of Medicine, I’ve been fortunate enough to work with world-class geneticists in our fantastic Molecular and Human Genetics Department. During my genetics rotations, I became familiar with taking family histories and drawing pedigrees, those family trees that help geneticists trace patterns of inheritance of various disorders, traits, and seemingly unconnected symptoms.

Getting the pedigree can tell you a lot about a person. Does she have any siblings? What does he know about his grandparents? Great-grandparents? What’s her ethnic background? How well does he know his cousins? His nieces and nephews? His grandchildren?

Physicians and other health professionals have the unique privilege of learning intimate details of their patients’ lives. As first-years learning the medical history, we squirm and laugh nervously as we are taught how to take a sexual history. Boys flounder as they try to ask a woman about her menstrual cycle. Yet I’ve come to believe that there is nothing quite as intimate as the family history, especially the version of it that a clinical geneticist gets from a patient.

I’ve had patients tell me that they were adopted, that their parents were unwed teenagers in a conservative town in East Texas who couldn’t possibly care for a child. I’ve heard the stories of how these patients connected, improbably, with their birth families. One patient found out he was at risk for a rare, deadly, inherited heart rhythm abnormality because his biological brother’s wife, neither of whom he’d ever met before, felt she had to contact every one of her husband’s relatives, when he died from that very same rhythm abnormality.

Patients with genetic disorders talk to their physicians about their concerns of passing on the disorder to their children. They worry if pregnancy will worsen their own health. Other patients, when I’ve asked them about their nieces and nephews, have sadly admitted that they fell out with that sibling decades ago, that they don’t know anything about that part of the family.

When we ask if anyone in their family has had children with a relative, as we must do with every pedigree, the responses vary quite a bit. Some patients’ mouths drop open in disbelief; others laugh nervously; still others matter-of-factly acknowledge that yes, their parents were first cousins, and so were both of their grandparents, and so on and so on.

One of my favorite parts of medicine is the conversations I get to have with my patients. Every time I take a family history, I’m reminded of just how much of a privilege it is to have these conversations. My patients tell me about their relationships, their concerns and fears, their family secrets. I’m lucky enough to be able to hear them speak.