Cassie Ruger hummed, somewhat tunelessly, as she dipped her shoulders and swayed her hips in a rhythmic motion. She’d seen plenty of “aunties”—both related to her and just older neighbor women—rock and sing to their children this way during her Caribbean upbringing. Within a month of adopting little Ginny, Cassie had begun to mimic her ancestors. The baby always calmed with a few minutes of the motion. The ability to soothe an infant and still carry-out work with her hands might as well have been written on her DNA.
“Speaking of DNA,” she crooned to the half dozing child, “let’s see what is written on yours.”
The sequencer displayed a flashing notification that its work was completed. Cassie side stepped over to the front of the terminal. She swiped the results icon to the tabletop in front of her, then expanded it with her fingertips.
“Huh. Well, there it is, right where we thought it would be. But…” Cassie reverted to humming as she expanded the image on the tabletop. She pulled another file down and opened it to compare the images side by side.
“Definitely chromosome 1. Chromosome 19 is unaffected.”
“Care to share?” Ben’s voice from just over her shoulder caused the petite medical doctor to jump. Ginny came awake with a yowl.
“Bells. Wear them,” snapped Cassie at the man who’d quietly entered her medical bay.
“Not in public, Liebchen.” He winked before his features took on a more serious expression. “So? What is right where you thought it would be?”
“A deformity on chromosome 1. The NPHS gene2, specifically. Mutations of this sort used to cause congenital kidney disease. It almost always led to kidney failure during early childhood. Genetic editing techniques eliminated the disease before we were born.” She shot Ben a teasing glance. “Well, before I was born, anyway.”
“Amusing. So, the mutation is inherited?”
“Presumably. The historic mutations of this gene were autosomal recessive—meaning both parents had to be carriers for a child to inherit it.”
“Ja, ja,” Ben muttered as he leaned over the enhanced images of Ginny’s chromosomes. “Have you scanned Marissa and Ryan Hill’s genomes?”
“I was about to start that process. Care to wait with me?”
Ben smiled softly at her. “There’s nowhere I’d rather be. Want me to take her?”
Cassie glanced down at Ginny’s dark curls. “No, she’s back asleep now.”
Ben pulled up a chair and stretched his long legs out in front of him, but oriented himself so that he wouldn’t be in Cassie’s way as she resumed swaying and side stepping. He took a minute to appreciate the sight of her. He wondered if she realized she had a stylus jammed into the back of her braided hair as well as one tucked behind her ear.
“So, this mutation used to cause that syndrome, but no longer?”
“The mutations were inherited and were eliminated via gene editing. While this mutation is in the same location, it obviously doesn’t have the same deleterious effects. She’s perfectly healthy with no symptoms of renal failure. Quite the opposite, actually. Her kidneys seem to be filtering the lorga from her bloodstream. They shouldn’t be able to. Our kidneys can’t filter it and thus the anemia. But that’s clearly a mutation on that chromosome. Look, see, this is what my NPHS gene2 looks like. Here’s yours. See this?” She’d swiped again to have the images appear in the air in front of Ben’s face. “That little sequence there?”
“Talk it out, Liebchen. What’s your thesis?” He closed his eyes, waiting for her to begin.
“This gene, NPHS, is one that writes the protein podocin. That’s the protein that forms the slit diaphragm in the kidneys—the mechanism for filtering our blood. So, what do we know?” Dr. Ruger ticked off points by raising fingers. “We know that there’s a mutation on Ginny’s NPHS gene2. We know that Ginny’s kidneys are, somehow, filtering the lorga from her bloodstream. We know that the filter in human kidneys is built by the protein produced by the NPHS gene.”
“And…,” Ben prompted without opening his eyes.
“And…” Cassie stared at the ceiling for a minute. “Oh, and we know that previous mutations on this gene inhibited proper filtration which led to renal failure. “
“It’s too early for conclusions. I need to run more tests.”
He folded his hands over his flat stomach after tugging at the vest he wore over his shirt. “But you already have a thesis. I know you do. Say it.”
“Ginny, somehow, possesses a genetic mutation that makes her uniquely suited for life on Dremiks.”
They exchanged weighted looks.
“How fortuitously coincidental.”
Cassie glared at Ben. “You don’t believe in coincidences.”
“And, yet, here we are. Unless you’re suggesting that Marissa and Ryan somehow re-wrote their genomes in anticipation of lorga poisoning leading to anemia.”
“Don’t be ridiculous,” she snapped.
He cocked his head to one side. “There’s an easy way to check.”
“How—oh. Compare Captain Hill’s DNA with Ryan’s. But autosomal recessive malformations aren’t always inherited by all offspring. I’d have to check his parents’ DNA files too. Which I’d need his permission to do.”
“Considering this is about their precious Inheritor, the Kigvans might let us use an emergency beacon.”
“You don’t really think Ryan and Marissa would go that far, do you? How would they even know to do that?” Cassie wrapped both arms protectively over the baby strapped to her chest.
“We know Ryan was in contact with the Valtoza. They genetically engineered the Dremikians to be a slave race. If they knew he was intending to have a child on the surface, perhaps they intended to ensure that child’s survival.”
“But there was no guarantee the baby would inherit the mutation, once introduced.”
“True.” Ben frowned. “Well, we’ve theorized ourselves into a cul-de-sac. We’ll ask Commander Myzme for permission to use an emergency beacon and get Captain Hill’s permission for the tests you want to run.” He rose and pulled Cassie into a gentle hug. Ginny squirmed between them. “Let’s go get dinner, ladies.”