“Easy,” said Leo. “If Ana and Carlos are both type A, they can’t have a type O child unless they’re both heterozygous AO.”
“Found in the estate papers,” she said. “Turns out Ana wasn’t AB at all. She was O negative her whole life. The AB was a transcription error made decades ago.”
The late afternoon light slanted through the lab windows as Maya pinned the last pedigree chart to the corkboard. “Okay, team,” she announced, uncapping a set of blood typing trays. “This is the Martinez family case.” lab activity blood type pedigree mystery
After running the simulations, Maya’s group confirmed that a type O child can only come from a type O parent or a heterozygous A/O or B/O parent. Since Ana was OO, Julian’s father must have contributed an O allele. That means Julian’s biological father was either type O, A, or B—but not AB.
When a rare blood type surfaces in a family pedigree, four lab partners must use serology and deductive reasoning to determine whether a long-lost relative’s inheritance claim is truth—or a clever lie. Story Draft “Easy,” said Leo
“Standard family,” Leo shrugged. “What’s the mystery?”
“But that’s not the only clue,” Dr. Reeves added. “Carlos’s blood type was confirmed type A—but Ana’s medical record from decades ago shows she was typed as type AB.” She was O negative her whole life
Here’s a short draft for a lab activity story titled Title: The Heirloom Type