A new test maps a newborn's entire genome, testing for all potential mutations that can cause cystic fibrosis. Previous methods of screening required several different tests and took more than four times the amount of time to receive results. Photo by St. Valentine Production/Shutterstock
STANFORD, Calif., Feb. 2 (UPI) -- Researchers at Stanford University have developed a blood test to screen newborns for all types of cystic fibrosis, which they say will allow doctors to begin treatment for the hereditary disease much earlier in life.
The new test is said to more accurate because it tests the entire cystic fibrosis gene for mutations in one step, unlike previous versions, and does so in half the time, researchers said.
Cystic fibrosis is an inherited disorder that causes mucus to build up in the lungs, pancreas, and other organs, and affects about 30,000 people in the United States each year.
The current test, which has been used since 2010 across the country, tests for an enzyme in the blood called trypsinogen. Thought it can be elevated for reasons beyond cystic fibrosis, most children with high levels are then tested genetically for other mutations in the cystic fibrosis gene.
The test, however, only looks for 40 mutations, whereas there are more 2,000 known versions of the mutation. If a common mutation is found, then the baby's genome is sequenced to confirm less common mutations.
The previous method of screening takes about two weeks, but the new one takes three days or less.
"Cystic fibrosis newborn screening has shown us that early diagnosis really matters," said Dr. Iris Schrijver, a professor of pathology at Stanford University, in a press release. "When the disease is caught early, physicians can prevent some of its complications, and keep the patients in better shape longer."
Researchers developed the new test, detailed in a study published in the Journal of Molecular Diagnostics, using the dried blood spots taken for documents when an infant is born.
The method was validated using 190 dried blood spots, and was shown to be 100 percent sensitive with a positive predictive value of 100 percent.
While individual states will need to approve the test before it can be put into wide practice, Stanford researchers hope to find similar methods for quick and accurate testing for other genetic conditions in babies.
"Ultimately, we would like to develop a broader assay to include the most common and most troublesome newborn conditions, and be able to do the screening much faster, more comprehensively and much more cheaply," said Dr. Curt Scharfe, a scientist at Stanford at the time of the study.