The Durand family — (Back) Heidi, Chad and Carson. (Front) Cullen and Oliver.

Nancy Edmonds Hanson

“Our boys are two of only 500 cases worldwide.” – Heidi Durand

One of Cullen’s countless physicians may have said it best. He told Chad and Heidi Durand, “Compared to this diagnosis, you’d have better odds of winning the Powerball.”
He was talking of the burden their 17-year-old son was born with. Known as 4H leukodystrophy, the vanishingly rare genetic disorder affects the nervous system. It attacks the white matter in the brain – the myelin sheath – that surrounds and protects the nerves, speeding the transmission of messages between cells.
Cully has never walked. He understands, but has never talked. And only in recent years, after regular trips to the Mayo Clinic and consultation with one of the world’s three leading specialists, have his parents – both teachers in Moorhead – learned the true nature of his challenge. It is baffling. It is progressive. And it is utterly incurable.
“We knew something was not right from the beginning,” Heidi Durand says now. “He was very floppy. He wasn’t meeting his developmental milestones. He wasn’t eating well – he would fall asleep while we were feeding him.”
They raised concerns at his 6-month checkup. Their pediatrician was reassuring: All babies have different timelines. “But,” Cully’s mother says, “we knew.”
Cully was the Durands’ second son. His older brother Carson was entirely typical – healthy, active, growing in every way. The younger boy was evaluated through Moorhead Public Schools, showing definite global delays. “The doctor ordered an MRI,” Heidi remembers. “That’s when it really hit us. They were looking at his brain.”
When the results proved inconclusive, they were sent to the Mayo Clinic, where Cully underwent a spinal tap and a battery of blood tests. But all came back normal. He remained a puzzle.
Yet the little boy was living life to the fullest. “He has a great sense of humor,” Chad reports. “Cognitively, he’s there with us. He’s mischievous — likes to joke and play little pranks. He loves laughing at our dogs.” Though Cully can’t speak, he communicates with a Tobi Dynavox, a tablet braced on his wheelchair that he controls with his eyes.
“That was the status quo for many years,” Heidi reflects. “For a long time, we never saw him losing abilities — just modest gains.” But then, in 2019, they started to recognize subtle losses. Cully could no longer control his power wheelchair reliably as he moved around their custom-built home. He began to have difficulty swallowing. He developed excruciating pain in his hips; his orthopedist discovered his hamstring muscles had grown so tight they were pulling the bones out of the sockets.
All along, Cully’s true diagnosis had remained a puzzle. It was finally solved a few years ago when Mayo clinicians conducted the extensive genetic testing that finally pulled all the pieces together. They finally pinpointed the cause – two mutations in the gene called POLR3A.
Leukodystrophy is hereditary, so Chad and Heidi were also tested. Both carry the mutated gene. With only one copy, it remains recessive; but when both parents carry it, they learned, their children have a one-in-four chance of inheriting the condition. “It just hit us out of the blue,” Heidi says. “We had absolutely no idea until we got the results.”
That hard-won knowledge came only a few years ago. In the meantime, Chad and Heidi’s third son, Oliver, now almost 10, was born.
“He didn’t show the same signs at first,” Heidi remembers. “He could sit up. He could do a lot that Cully never could. He walked, but not until he was 2. He started talking at three. Deep down, I think I knew.”
The same genetic test confirmed what she says she “knew but didn’t want to know”: Ollie, too, has 4H leukodystrophy. Not just one, but two of the Durands’ three sons number among victims of the unimaginably rare disease – a diagnosis so new and so rare that few doctors know much about it. “So they doctor the symptoms,” Chad observes, “because there’s no treatment for the disease itself.”
He says that, while their two younger sons share the same diagnosis, there are differences. Ollie walks with the help of a walker; Cully has always needed a wheelchair. Ollie’s cognitive skills seem more impacted than his brother’s. Their personalities are distinctly different. “Cully is quiet, sensitive. He picks up on other’s emotions,” his father says. “Ollie is feisty and boisterous.”
Like Cullen, Oliver is very small for his age. While he can still walk with assistance, his parents see signs that he’ll soon be using a wheelchair. The disease, after all, is progressive. It is also life-limiting.
And life-changing. While Heidi and Chad celebrate 21-year-old Carson’s achievements at Arizona’s Grand Canyon University, where he’s majoring in elementary education and participating on a disc golf team headed to the national championships, their lives at home are much different.
Both younger boys attend school. Oliver is a second grader at Dorothy Dodds, where his father teaches fourth grade, and Cullen is in his junior year at Moorhead High. A nurse assigned by the school arrives at 7:55 each morning to transport Cullen to school, where she stays at his side throughout the day in his special education room. Oliver’s day is divided between his regular classroom and special ed services, including physical and occupational therapy.
While Heidi has taught full-time at M State for more than 20 years, her “classroom” is online. She’s grateful: “I couldn’t do this any other way,” she points out. “Teaching online means I can be here when Cully isn’t well enough for school.”
Caring for a child with a complex, life-limiting disease is a 24-hour job. Caring for two? “Twice the strain,” Chad admits. “People who know about our boys tell us, ‘You guys were born to do this,’ we weren’t. We have learned how to care for them and adapted because we have to. When a situation presents itself, we fight for them. You can’t let it break you down.”
What do they miss most about this life that has been thrust upon them? “Watching them play sports,” Chad finally comments. (He coaches 7th and 8th grade boys and girls basketball and track when he’s not in his classroom.)
“We used to have a blast camping when Cully was little,” Heidi adds. “We had a pop-up camper, went geo-caching, had a great time in the woods.” Their sons’ growing health issues ruled those excursions out years ago.
While they occasionally get away with the help of respite caregivers, the couple never travels together these days. “When Heidi goes, I’m home. If I travel, she’s home.”
Heidi has connected with some of the rare parents who share their challenges through social media and the Yaya Foundation, established by parents who lost a leukodystrophic daughter at the age of one. They share their experiences with the few others who have the same concerns, the same love and the same occasional flashes of joy in caring for children who are as unique and as special as they are rare.
Why have the Durands chosen to talk about their sons now? Feb. 29 is National Rare Disease Day, the once-in-four-years occasion when they and their counterparts seek to bring attention to conditions most others have never heard of, much less understood.
“We want to raise awareness. We want to generate support for a disease that’s so rare that little or no research is being done,” Heidi asserts. “There are no treatments. There is no cure. This is only the beginning.”