Danny’s blood type, combined with the inheritance patterns of his parents, shows he is the only one who fits the specific evidence left at the scene (often a blood-stained piece of evidence or a specific genotype mismatch with other siblings).
The older versions often omit Rh factor. Add a fourth claimant with Type A- or B+. Then discuss how Rh- mother carrying an Rh+ baby can cause hemolytic disease of the newborn (HDN), adding a medical ethics layer to the mystery.
The Blood Type Pedigree Mystery challenges students to apply Mendelian and non-Mendelian genetics to a real-world scenario (such as a hospital baby mix-up or a forensic inheritance dispute). By completing this lab, students will:
Answer: They show relationships across generations. They help determine if a trait is dominant or recessive.