The advent of new screening technologies in the late 1990s vastly increased the number of potential diseases that could be detected with a blood sample easily obtained by pricking the heel of a newborn. Genetic testing of newborns got another shot in the arm in 2005 when the American College of Medical Genetics called for mandatory screening of 29 conditions and 24 sub-conditions. By 2009, all 50 U.S. states and the District of Columbia screened for at least 21 of the 29 recommended conditions, and the full recommendations had been adopted by 44 states, including California.

Other countries have since adopted genetic screening, but they test for fewer conditions and add new conditions more slowly than the U.S. The study findings cast doubt on the medical efficacy of the battery of screenings administered widely in America, the researchers said.

"Expanded newborn screening has called into question whether screening targets correspond to actual diseases or just benign forms of human variation," Buchbinder said.

"There are many more positive screenings than were anticipated based on the incidence of the diseases in the general population," Timmermans added.

Nobody knows the number of families who fall into the patient-in-waiting category, but it is assumed to be a relatively small number. Still, the number is much larger than was anticipated when screening for a wide range of conditions began in 2005, the study argues.

The researchers also suggest the need for increasing the speed with which follow-up tests are administered so that parents of patients-in-waiting spend less time wringing their hands.

"When the American College of Medical Genetics advocated for the expansion of newborn screening, they argued that the societal benefit of newborn screening would be the avoidance of diagnostic odysseys in which parents of kids with rare diseases travel from doctor to doctor in an attempt to find out what is wrong with them," Timmermans said. "Our study shows that, in fact, the expansion of newborn screening has created a new population on diagnostic odysseys ” the parents of these patients-in-waiting. Now we need to figure out how to dramatically shorten or eliminate this unexpected and stressful journey."

Source UCLA