The widely held belief that you can always rely on family may be especially true when it comes to your risk for certain diseases, new research shows.
Researchers led by Dr. Charis Eng, chairman and founding director of the Genomic Medicine Institute of the Cleveland Clinic, found that a thorough family history better predicted the risk for developing certain cancers than genomic screening did.
"Evaluation of family health history still remains to be the gold standard in personal disease risk assessment," Eng said in a news release.
Genomic screening isn't the same as genetic testing. Genomic screening involves evaluating portions of a person's genetic makeup to determine whether there are genetic variants that put people at higher risk to develop particular diseases or traits. In genetic testing, people are screened for the presence of an entire gene known to cause a disease.
Eng and her colleagues assessed 44 people's risk for developing breast cancer, prostate cancer and colorectal cancer by obtaining a complete family health history and also by using a direct-to-consumer personal genomic screening tool. They presented their findings at the annual meeting of the American Society of Human Genetics.
A comparison between the two methods showed that they did not often place people in the same risk category for the three kinds of cancer. Researchers also found that personal genomic screening did not identify nine people who were found to be at high risk for colon cancer because of a previous family history.
"Study after study has shown that a well-taken family history can be one of the most powerful predictive factors for preventative health and health maintenance," said Dr. Kandamurugu Manickam, a geneticist at Ohio State University's Center for Personalized Health Care in Columbus.
"It has always been my contention that the well-taken family history is the most sophisticated genetic test," said Dr. Ronald Bachman, chief of the Department of Genetics at Kaiser Permanente Oakland Medical Center in California.
In addition to helping assess disease risk, doctors say knowing a patient's family history can help offer insight into how someone will respond to certain treatments.
Dr. Marjorie Bowman, professor of family medicine and community health at the University of Pennsylvania School of Medicine in Philadelphia, said, "I told a patient never to take a statin drug as her brother went into marked liver failure within a few days of taking a statin drug; a rare event that seems highly likely to have a significant genetic component."
Although they cost little or nothing to do and patients can easily obtain the information, one barrier to family histories is the time constraints primary care doctors are under. While they agree that family histories are important, there's often not enough time to get them.
Another problem with family histories is that primary care doctors don't always know how to take a thorough family history, according to medical specialists. They also say that even electronic medical records do not allow for a proper medical history and subsequent assessment of risk.