Genetics discoveries could lead to disease prediction
October 14, 1997
Web posted at: 11:09 p.m. EDT (0309 GMT)
(CNN) -- As researchers rapidly uncover genetic clues into
the role genes play in our health, your doctors one day may
be able to read your full genetic profile and detect disease
before it starts.
This week's Journal of the American Medical Association
(JAMA) reveals a glimpse of some of the latest genetic
discoveries. The pioneering studies are the result of the
Human Genome Project, a 15-year international effort to map
all genes now in its seventh year.
"The human genome initiative is an initiative whose goal is
to define resources that can be used in the study of human
genetic disease," said Dr. Margaret Pericak-Vance of the Duke University Medical Center. "It's had a tremendous impact on genetic research to date." (170K/15 sec. AIFF or WAV sound)
Currently, there are more than 450 tests for human genetic
disorders, and that number is expected to rise dramatically
by the conclusion of the project.
"What genetic testing will tell you is whether you carry
susceptibility or are predisposed," said Dr. Donna
Shattuck-Eidens of Myriad Genetics Inc., a genetic testing
company involved in the project.
She stressed it will not diagnose cancer the way a mammogram
will detect cancer. "What genetic testing allows you to do is
know what your risk is, then make lifestyle decision based on
Researchers already know that 5 to 10 percent of breast
cancer is due to an altered copy of one of two genes known as
BRCA1 and BRCA2. That knowledge might help physicians better
determine a patient's risk for developing breast cancer.
There are also genetic advances in Alzheimer's disease.
"We've learned more in the past decade about Alzheimer's
disease than we learned in the past century since it was
first described," said Pericak-Vance.
New knowledge about Alzheimer's is reported in the same issue
of JAMA. The study reports that the gene that makes certain
people susceptible to the disease after age 60 probably hides
within chromosome 12, one of the string-like structures that
Genetic findings like that can lead to new treatments,
screening tests, and a better understanding of why some
people get certain types of diseases and why some don't.
Health professionals are concerned about how to integrate
this growing body of knowledge into clinical practice. For
example, a recent study of colon cancer testing revealed
nearly one-third of physicians who delivered DNA test results
did not fully understand their meaning.
To correct that, Pericak-Vance predicts a growth in education
of physicians from the medical school level through
practicing primary care physicians. "The diseases we're
looking at now, in which genetics will play a role, are the
common diseases," she said.
Medical Correspondent Dr. Steve Salvatore contributed to this