Never Let Me Go (Camren/Norminah)

Chapter 7: The Gift of Heredity

"Hey Lauren, can I ask you something?"

It had been an uneventful weekday, starting with a morning chock full of classes, an afternoon of labs and an evening at the gym. Lauren had wrapped up a workout with her roommate, and now stood topless in the middle of the empty changing room. The girl was facing away with her arms over her chest as she tried to decide which outfit sitting in the open locker smelt least like sweaty shoes.

"Sure Mani, anything."

"There's a paper I have to write on the psychology of eye colour, and I figured it would be good to get a little bit of a biologist's point of view. And I think we both know that the only biology I could tell you is that you need a boy and a girl to make a baby."

Lauren rolled her eyes, smiling lightly as she reached for a bra. "First off, that's not true. You need a boy and a girl to have a baby, you can make one any way you want. Second, what did you want to know? I've done my share of neuroanatomy. It was the the single most fun and boring class I've ever had at the same time."

Normani made a noise, seating herself on the thin bench and pulling out a clipboard covered with papers. "So I need to explain how a kid gets a certain eye colour from their parents. Is it like some kind of genetic lottery?

"Kind of." Lauren hooked a navy blue bra around her body, dropping the towel. "Eye colour is linked to a number of different genes, I'd have to check my notes to give you the exact ones... I know there's OCA2 but I can't remember the others."

"I'm already regretting this." Her roommate mumbled back, jotting something down on the board. "Okay, keep going."

"Eye colours can range from a really dark brown to a really light blue. The colour you get depends on a series of single-nucleotide polymorphisms in the genes and their neighbours, which in turn affects the amount of melanin pigment in the iris. Brown eyes have a lot of the pigment, bluer eyes have less." Lauren explained, shrugging on a t-shirt and a pair of shorts, running her fingers through her long damp hair. "It's actually kind of cool, we used to think that eyes followed an inheritance pattern, where brown eyes were dominant and blue eyes were recessive. That meant that only parents with blue or green eyes could have babies with blue or green eyes."

Normani looked up. "I guess you prove that theory wrong."

"That I do." The Latina gave her friend a sweet smile. "So in your paper, be sure not to make that mistake. Kids only get the genes from their parents, the amount of melanin in the eye is affected by polymorphisms that only they're responsible for. Multiple genes are involved, so we can't say for certain eye colour follows the same track as something like Huntington's Disease or sickle cell anemia."

"I'm guessing those are more genetic." Normani glanced up again.

"Yeah." Lauren frowned in the mirror and tugged her shirt off, grabbing another one and giving it an inspective sniff. "I love pathology and disease, it's one of the most research-forward fields right now. Camila could tell you more though."

"No, I think you've done more than enough." Normani made a soft sighing nose, clicking her pen and starting to nibble on the end. "The last time I asked for information from Camila she locked me into a two hour debate over something called the crisper locus."

C-R-I-S-P-R." Lauren clarified, looking over her bare shoulder. "We're learning to genetically alter pig organs and match the MHC complexes with humans so we can eventually start doing transplants wi—"

"Bye nerd." Normani was on her feet with a towel over her shoulder, halfway out of the change room before Lauren could even turn around. "You're lucky I don't stuff you into a locker and leave you there!"