How to use the linkage lod score calculator
Find the LOD score for linkage between two genes from recombinant and non-recombinant offspring counts. Enter recombinant offspring, non-recombinant offspring, recombination fraction tested in the fields above; the lod score, evidence for linkage are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “LOD score linkage”, “genetic linkage test”, “recombinant offspring LOD”, “calculate linkage lod score”, “find lod score”.
Formula
Variables
- R — Recombinant offspring
- NR — Non-recombinant offspring
- th — Recombination fraction tested
Worked example
With recombinant offspring = 2, non-recombinant offspring = 8, recombination fraction tested = 0.2, the calculator gives lod score ≈ 0.8370798; evidence for linkage ≈ Not yet conclusive text.
Frequently asked questions
What is the linkage lod score calculator used for?
Find the LOD score for linkage between two genes from recombinant and non-recombinant offspring counts. It helps with questions such as “LOD score linkage”, “genetic linkage test”, “recombinant offspring LOD”.
What is the formula for the linkage lod score calculation?
LOD score = log10(th^R × (1-th)^NR / 0.5^(R+NR)). Evidence for linkage (text) = [LOD score]>=3?"Linked (LOD 3 or more)":"Not yet conclusive". Here R is recombinant offspring, NR is non-recombinant offspring, th is recombination fraction tested.
What inputs do I need for the linkage lod score calculator?
You need recombinant offspring, non-recombinant offspring, recombination fraction tested. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the linkage lod score calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the linkage lod score result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.