Life with SMA: Patient, advocates weigh in on rare genetic disorder

May 1—At the age of 23, Chloe Caldwell is learning to drive.

She had her first lesson in mid-April, but won't be able to get back in the driver's seat until the summer. She has to wait until her new set of wheels is modified so it can be operated with two paddles.

Caldwell was born with Spinal Muscular Atrophy, a genetic disorder that, according to the Centers for Disease Control and Prevention, affects approximately 1 out of every 10,000 people.

The rare disorder happens when a segment of the survival motor neuron 1 gene is missing. When that happens, the gene isn't able to make protein, resulting in motor function loss.

There are different levels of SMA with ranging severity often linked to how old the person was when their symptoms began to manifest.

In Type 1 SMA, which comes before infants reach 6 months, it can affect a baby's ability to swallow, breathe, sit and walk. Without treatment, it can also result in death.

Caldwell has Type 2 SMA, which usually comes as infants are learning to walk.

Her two brothers also have Type 2 SMA. The eldest was able to walk until he was 18, and the youngest was able to walk until he was 12. The disorder progresses, though, Caldwell pointed out. Patients begin to lose their muscles.

It's uncommon for SMA patients to have siblings with the disorder, she added.

"It's very rare, the disease itself. Both parents have to have the gene that makes it," Caldwell said. "But it's crazy because there's a lot of other families out there, SMA families, where one kid has it but the others don't."

An organization called Cure SMA works to support programs and individuals in the SMA community. It also funds and directs research for treatment.

Based on 2020 birth and population data for the state of Indiana, the organization estimated 248 people in the state have some form of the disorder. Approximately seven people are born with it in Indiana every year, the organization estimated, and 135,711 people statewide are carriers.

Life with SMA

Caldwell said her life isn't really much different from other people's, she just needs help with certain things since she isn't able to transfer herself from an electric wheelchair or lift anything heavier than three pounds.

She's lived on her own for roughly five years. A home health aid comes over and helps her.

"I would say the stuff she can do, most people take for granted," her boyfriend Caleb Bunch said. "For her lifting three pounds, that's like me trying to deadlift 150. So she gets really tired really fast."

Caldwell added tasks that might take someone without SMA 10 minutes to complete can sometimes take her an hour.

She plans to resume classes at Ivy Tech in the fall, where she's been working on a degree that will let her become a social worker or psychologist.

"I want to help people who are in my situation and help people who have been through traumatic things," Caldwell said, later adding "that's what I want to do in life, is to help people."

While at home, she likes to make art and spend time with her pets. Caldwell also likes to travel.

She and Bunch go to Michigan from time to time, have stopped by Chicago and recently got back from Las Vegas.

Tennessee is Caldwell's favorite, though. She calls it her second home.

It's the first place she plans to drive when she finally gets her driver's license.

"There's still so much to learn, but it's really cool," she said.

Caldwell explained the car is operated with two paddles on either side of the driver's seat. The right hand paddle steers the car and the left hand paddle controls the acceleration.

It was raining when she took her first lesson, but she wasn't too nervous. The difficult part, she said, has been getting a car.

Caldwell won a van six months ago through the Muscular Dystrophy Family Foundation. Hundreds of people apply for the donated vans every year, she said, but just three were able to receive one.

Indiana Vocational Rehabilitation is paying for the van to be converted, but it'll take a while since it has to become a passenger van first, then modified so Caldwell can drive it.

Bunch chimed in the van costs roughly $150,000. It isn't a fancy sports car, he added, just something to get Caldwell to school or work and back. He pointed out the same amount of money could buy a house.

"They definitely make the world way more difficult for disabled people," Caldwell said. "It's so unfair."

Treatment and detection available

Kenneth Hobby, president of Cure SMA, wrote in an email to the Tribune that roughly 7 million people across the U.S. are SMA carriers and it can show up in later generations. People are able to be screened for the disorder, he added.

"It can have a huge impact on an individual, the family, and also the broader community beyond," Hobby added. "The successful progress we have had in SMA is looked at as a model for developing effective therapies for many other diseases, and some of these can be quite common genetic and neurological."

There are three SMA treatments that have been approved by the FDA, with several others in clinical development. Caldwell takes a liquid medicine orally every day that's supposed to stop the progression of her SMA.

In some cases, she said, it can slightly reverse the effects of SMA. Caldwell has regained a bit of strength in her arms, but knows others who haven't regained any muscle.

Without the treatment, Caldwell estimated she would die before turning 40.

"They've come out with so many drugs that weren't a thing when I was a kid," she said. "This medicine didn't even come out until four or five years ago, and now there's one that is for babies that can cure it."

The children have to get treated while in their infancy, though.

"The sooner that SMA can be detected then there is the best opportunity to intervene and stop further irreversible damage to the nerve cells," Hobby wrote in an email. "We now have very powerful treatments that are approved and available that can stop the course of the disease and prevent further damage from happening."

Indiana became the fourth state to start screening for SMA and severe combined immunodeficiency after Gov. Eric Holcomb signed Indiana House Bill 1017 in 2018. The screening is mandatory unless parents submit written objection for religious beliefs.

According to Cure SMA, more than three-quarters of the states have now implemented newborn screening for SMA.

Hobby explained people can help fight against the disorder by supporting research and development toward treatment.

"We have an amazing local community of supporters in Indiana — working to raise funds and conduct advocacy," he wrote. "There is great progress in the state with recent implementation of newborn screening, and access to the current treatments."

James Bennett III can be reached at 765-454-8580 or james.bennett@kokomotribune.com.