1. Tardigrade
  2. Question
  3. Biology
  4. In a polygenic cross Aa Bb Cc × Aa Bb Cc, the phenotypic ratio offspring is 1: 6: 'X': 20: X: 6: 1. What is the value of 'X'?

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. In a polygenic cross $Aa\, Bb\, Cc \times Aa \,Bb \,Cc$, the phenotypic ratio offspring is $1 : 6 : 'X' : 20 : X : 6 : 1$. What is the value of $'X'$?

Principles of Inheritance and Variation

Solution:

In a polygenic trihybrid cross $(AaBbCc \times AaBbCc)$ the phenotypic ratio is $1 : 6 : 15 : 20 : 15 : 6 : 1$.