Domesticating Dragons – Snippet 08
I was twelve when I first got interested in genetics. My brother Connor was ten, and we spent every waking minute together. That’s probably why I noticed the little changes. He started to tire more easily, whereas I had boundless energy. He couldn’t jump as high as he used to.
No one believed me, though. I tried telling my mom how there were some days when he couldn’t keep up with me. And that he had trouble getting to his feet sometimes. He’d get on all fours, then push his butt up in the air, and finally come back on his thighs. It looked weird. But she worked all the time to support us. Every night when she got home, I think she was just grateful to see we were still in one piece. She didn’t see Connor the way I did.
Right up until the day he fell while we were out playing and couldn’t get up. She believed me that time. She called an ambulance.
Somehow, we bypassed the emergency room and landed in something called the PICU. Pediatric Intensive Care Unit. That was probably a good thing, because it brought Connor in front of a rarity: a doctor who actually gave a damn.
She was an older lady, short and sharp-eyed. She wore a bright floral blouse beneath a well-worn lab coat. If it weren’t for the coat and the stethoscope, I’d have mistaken her for someone’s grandmother. She bustled in while a nurse was checking Connor’s vitals. “I’m Dr. Miller. Want to tell me what happened?”
“They were playing outside,” Mom said. “He fell and couldn’t get back up.”
“How hard did he fall?”
Mom looked at me, and so did Dr. Miller. I squirmed under their gazes. “Not that hard. It was more of a trip.” I didn’t volunteer the fact that I was the one who tripped him.
Connor didn’t either, but made a face at me behind their backs. The nurse left, and Dr. Miller began her own examination.
“He’s behind in his growth curves,” she said.
My mom waved this off. “He’s always been small for his age.”
I smirked at Connor, who stuck out his tongue at me.
“Any staring spells or seizures?” the doctor asked. Her East Coast accent stretched out the vowels, which made her a little hard to understand.
“None that I saw,” Mom said. She looked at me for confirmation.
I shook my head.
Dr. Miller took out a reflex hammer and tapped Connor’s knees. His legs jerked out, but only slightly. She frowned and lifted his legs one at a time to examine his ankles. “Any problems with walking or running?”
“He runs slow,” I volunteered.
Connor punched my arm.
“His heel cords are a little tight,” Dr. Miller said.
“Is that significant?” my mom asked.
“By itself, no,” Dr. Miller said. “But with sudden ataxia and the diminished reflexes, it could be the early signs of a muscle disease.”
“Oh my God,” Mom whispered.
“Many of them tend to run in families. Are you the biological mother?” the doctor asked.
“Of course, I’m his god–” she began, but caught herself. “Yes. Why would you ask that?”
“They can run in families. Have you had any health issues? Especially muscle weakness or problems walking?”
“What about fatigue?”
“Who doesn’t have some fatigue?”
Dr. Miller barked a laugh. “Fair point, Mrs. Parker. Does his father have any health concerns?”
Connor and I waited for the answer, both of us holding our breath. Mom never talked about our dad. He took off when I was four. Connor had no memory of him. I thought I did sometimes–vague flashes of a deep voice and dark beard–but I couldn’t be sure.
Mom frowned. “We’re not in touch. But I don’t think so.”
“I’d like to do further testing to rule out genetic disease.”
“What does that involve?” Mom asked, in a tone that meant, what does that cost?
“We’d look at a panel of a couple hundred genes. Have you unlocked their sequence data?”
Every newborn in Arizona had their genome sequenced, though the results were “locked” in a data vault, only to be consulted if there was a problem.
“No. I don’t like the idea of that information being out there,” Mom said.
“It will stay confidential, as part of your medical records.”
“Can you guarantee there won’t be some kind of a data breach?”
Dr. Miller paused. “No. But your genome is like the money in your bank account. You have to take it out to use it. Otherwise, what’s the point?”
“Are there any alternatives?” Mom asked.
“A muscle biopsy. It could confirm the diagnosis, though it’s a more primitive test.” She lowered her voice. “Not to mention uncomfortable.”
In the end, my mom gave over. She signed the papers to unlock our genome data for genetic testing.
The following week, the pediatrician called with news: Connor had a genetic variant in a gene called BICD2. That was short for bicaudal D homolog 2, and mutations in it caused a dominant form of spinal muscular atrophy. Mom and I didn’t have the variant. Dr. Miller explained that it was probably a newly arisen change, a so-called de novo mutation. Every person has fifty or sixty de novo mutations that they didn’t get from their parents. It’s a quirk of nature: The low-but-measurable error rate from copying our genetic code. Most mutations happen outside of genes, so they have no serious consequences. Connor was just unlucky.
There was a problem, though. Connor’s mutation had never been seen in a muscular atrophy patient. Or in the DNA of healthy people, for that matter. The genetic testing laboratory classified it as a Variant of Uncertain Significance, or VUS. It might cause disease, or it might not. The lab couldn’t say for sure. Insufficient evidence, they claimed. They wanted to know if it would be possible to get a sample from Connor’s biological father.
“Never gonna happen,” Mom said.
Dr. Miller understood, but her hands were tied where the diagnosis was concerned. Connor’s variant remained a VUS.
In some ways, that almost made things worse. Without an official diagnosis, we didn’t know what to expect for Connor’s future. Some mutations in his gene caused only mild muscle weakness. Others caused a severe and progressive disease. The uncertainty hung over our family like a specter. Maybe he had the disease and would start getting worse. Maybe he had something else entirely. BICD2 disease had no cure. Because of the uncertainty, Mom couldn’t get him into any clinical trials. All she could do was sit back and watch.
Twelve-year-old me called bullshit on that. If there was no way to prove that Connor’s mutation caused disease, well, I’d just have to invent one.