Punnett square
Enter both parents’ genotypes for one to three genes. The result updates as you type.
Nothing you enter is sent: your data stays on your device.
Used to estimate the number of pups per genotype.
Result
Enter the mother’s and the father’s genotypes, or start from an example.
The tool gives genotypes, not phenotypes. It assumes genes inherited independently (no genetic linkage), autosomal (no sex linkage) and with no lethal genotype. These proportions are averages: a real litter varies.
How it’s calculated
Method
The tool lists each parent’s possible gametes, crosses them, then groups identical genotypes. The proportions are averages: a real litter often departs from them.
Mouse notation: two alleles separated by a slash (Tg/+, fl/fl, +/−). The + is the wild-type allele, the − a null allele, and the non-wild-type allele is written first.
By default, the target is the rarest genotype among those carrying the most non-wild-type alleles. Choose another in the table.
Pups on average = proportion × litter size, rounded to one decimal.
Limits
- Genes are inherited independently (no genetic linkage).
- Genes are autosomal (no sex linkage).
- No genotype is lethal.
- Alleles pass on unchanged (for example, no germline recombination of a floxed allele by Cre).
- Genotypes only: the tool predicts no phenotype.
- One to three genes: beyond that, the grid exceeds 64 squares.
Sources
- The Jackson Laboratory, Colony Planning: expected offspring genotypes for one gene (homozygous and heterozygous crosses). Crosses on several genes combine these by Mendel’s law of independent assortment.
These tools help you plan. They replace neither your protocol nor your animal care committee.