Lab Activity Blood Type Pedigree Mystery !new! Jun 2026

: Mapping out generations to determine the likely genotypes of suspects based on their parents and children. 🗝️ Common Solutions & "The Twist"

The purpose of this lab was to utilize ABO blood typing and pedigree analysis to resolve a familial mystery. Through the analysis of agglutination, the phenotypes of the subjects were determined. By applying Mendelian genetics and the laws of segregation, it was determined that a Type A father and Type B mother can produce a Type O child, provided both parents are heterozygous ($I^A i$ and $I^B i$).

“But here’s the twist,” Dr. Reeves said. “Carlos is not the father.” lab activity blood type pedigree mystery

The results of the lab activity present a complex genetic puzzle. Initially, the blood types of the parents (Type A and Type B) seem compatible with almost any blood type in the offspring, provided the parents are heterozygous.

The "Mystery" usually hinges on a few genetic "impossibilities" that students must catch: : Mapping out generations to determine the likely

When students find an inconsistency—such as a child having an allele that neither parent possesses—the "mystery" is solved. The claimant is a fraud, or the hospital switched the babies! Why This Activity Works

Pedigree charts are diagrammatic tools used by geneticists to trace the inheritance of specific traits through generations. Standard symbols include squares for males, circles for females, and shaded or open symbols to represent phenotypes. By applying Mendelian genetics and the laws of

Maya examined Julian’s alleged blood type on the intake form: .

Would you like a printable student worksheet to accompany this story, including data tables and analysis questions?