Nineteen-year-old Declan was in his early teenage years when his legs began failing him.

While the cause was not apparent, his symptoms were consistent with unknown leukodystrophy, a degenerative condition affecting the brain, spinal cord and nerves. By the time he reached his late teens, it was expected Declan would start to experience cognitive delay, loss to his speech and motor function, and seizures.

DNA testing found a suspicious genetic variant, however was unable to provide... read more.