Researchers say sequencing genomes can lead to quicker diagnoses and effective treatments for more than half of children affected by brain disorders

Mya Burkhart was only six months old when she went into cardiac arrest. Fortunately, she was in the hospital when it happened, brought there by her parents because she had trouble breathing. It was her eighth or ninth visit to the emergency room for her respiratory problems, but each time the doctors had sent the Burkharts home with more questions than answers.

Mya wasn’t developing at the normal rate. She couldn’t lift her head and wasn’t responding to people and things around her. Doctors thought she might have a muscle disorder, but her other symptoms did not fit with that diagnosis.

After her heart scare, Mya spent three weeks, including her first Christmas, in the ICU on a ventilator. “I couldn’t pick her up or anything,” says her mother Holly. Still unable to solve the mystery of what was ailing her, the doctors finally suggested she have her genome tested. Maybe, they hoped, her DNA would offer some clues about why she wasn’t growing normally.

MORE: The DNA Dilemma: A Test That Could Change Your Life