Right after Astrea Li was born, she went into cardiac arrest, not just once, but repeatedly. It was all her doctors at Lucile Packard Children's Hospital Stanford could do just to keep her alive. Soon, a far-flung team of researchers joined together to solve the mystery of what was causing Astrea's severe heart arrhythmia.
As I wrote in a news release:
At a regular weekly clinical meeting of Stanford Medicine's Center for Inherited Cardiovascular Disease, Euan Ashley, FRCP, DPhil, a professor of medicine and of genetics, and James Priest, MD, an instructor in pediatric cardiology, heard about the case and knew they could help.
'We realized how sick this child was,' Priest said, 'and we had a new tool -- rapid whole-genome sequencing -- that could make a faster and more comprehensive diagnosis than the available clinical genetic testing. So that night I went and talked to the parents and the rest of the team, collected a blood sample and we started the test.'
Now, the Stanford-led team has solved the mystery. Astrea's heart malfunctioned because a tiny minority of the cells -- just 8 percent -- carried a deadly genetic mutation that arose spontaneously during development. Neither of her parents had the mutation and 92 percent of her cells were fine as well.
The discovery that this mixture of mutated and healthy cells, called mosaicism, could cause such severe effects opens the way for researchers to identify other similar mosaic genetic diseases.
And, how's baby Astrea now? Doing well. She's three and loves cartwheels.
Previously: When ten days = a lifetime: Rapid whole-genome sequencing helps critically ill newborn and After weeks of waiting, baby gets heart
Photo of Astrea, her parents and James Priest by Norbert von der Groeben