A few months ago Adelaide teenager Orlando Lupoi looked up at the night sky and discovered something he had never seen before.
"I could see, like, speckles of light," he said.
"Then I asked my brother, 'Are those stars?', and he said, 'Yeah'."
Before that night, the 16-year-old — whose rare genetic condition had left him facing blindness — never understood how people could see celestial light.
To finally recognise a star was, he said, a "pretty amazing" experience.
When Orlando got home, he went straight to tell his mum Susan Lupoi, who still gets emotional thinking about the conversation.
"I couldn't believe it, it was quite overwhelming," she said.
"His sister and I were a bit emotional about it and quite excited for him."
Orlando has a rare genetic condition called Leber congenital amaurosis, which affects about one in 30,000 to 40,000 people.
It impacts the eye's retina and its ability to process light.
From a young age, Orlando was not bothered looking directly at the sun.
The condition was causing his vision to gradually become worse, and doctors told him he would be blind by age 20.
"My husband and I had this thought about him seeing black for the rest of his life and that was really hard to take," Ms Lupoi said.
Genetic 'spelling error' to blame
The condition also caused Orlando's vision to be particularly poor at night, which made night-time social activities — such as going to the movies — difficult.
"Some events I wouldn't attend because it would be too dark and I didn't really want to go out of my comfort zone," he said.
Head of the Paediatric and Reproductive Genetics Unit at the Women's and Children's Hospital, Chris Barnett, said the rare condition was caused by a "spelling error" in his RPE65 gene.
Both parents have to carry the "error" for the condition to be passed on to their children, he explained.
Professor Barnett said finding the first "mistake" was relatively easy, but it took much longer to find the second.
"It's like trying to find a spelling error in a book," he said.
"The second one was a spelling error that was a bit more like the two versions of the word 'there/their'."
'Life-changing' gene therapy treatment
But in 2020, a new treatment, called Luxturna, was approved for use in Australia, providing a breakthrough opportunity to save Orlando's sight.
"There's one treatment in the world for this form of eye disease and it's this particular gene that has the error in it, that Orlando had," Professor Barnett said.
"And that therapy had only become available for the first time in Australia in 2020.
"No other genetic eye disease has such a specific gene therapy available.
"So, everything sort of came together to give Orlando a chance at sight."
Professor Barnett said the treatment involved an injection into the back of the eye, through the eyeball, to deliver a healthy copy of the gene to the affected cells.
"Once the functional RPE65 gene is delivered … it helps the retinal cells to produce missing protein, which is necessary for the conversion of light into electrical signals that are sent to the brain," he said.
Orlando travelled to Sydney Children's Hospital for the procedure last September.
He became just the sixth person in Australia to undergo it.
"It's pretty life-changing knowing that I'm not going to go blind anymore," he said.
