The cross
The organism has two chromosomes (n = 2) carrying seven SNP markers, A–D on chromosome 1 and E–G on chromosome 2. At each marker Parent 1 has one DNA base and Parent 2 has a different one, so the F1 is heterozygous everywhere. The tester can only pass on Parent 2 chromosomes, so each offspring's genotype shows exactly which gamete the F1 made.
Make testcross offspring
Simulate one offspring to watch the F1 make a gamete.
Testcross population
No offspring yet.
Recombination frequency between markers
Recombinant offspring ÷ total offspring, counted from the marker genotypes. Tap a square for details.
Recombination frequency and distance
Each dot is one pair of markers. Pairs on the same chromosome are placed by the distance between them; pairs on different chromosomes are grouped at the right.