Two genes, C and D, lie on the same chromosome. In a mapping experiment the recombinant frequency between them is 35 %. The observed double‑crossover frequency is 12 %. What are the coefficient of coincidence and the interference?

Step-by-step solution

1. Expected double‑crossovers if intervals act independently: $(0.35{)}^2=0.1225$ or 12.25 %.
2. Coefficient of coincidence $=\frac{\text{observed}}{\text{expected}}=\frac{12\%}{12.25\%}=0.12/0.1225\approx 0.98$.
3. Interference $=1-\text{coefficient}=1-0.98=0.02$.

Concept tested: Coefficient of coincidence and interference calculation

Published 24 September 2026 · How this solution was prepared and checked