You want to determine if two genes (Neon shell and bioluminescent body) are linked in your new species of exotic snail. Genomic sequencing is out of reach, alas the grant reviewers at NSF do not see the awesomeness of your little snail and deny your grant, so traditional breeding it is! Neon shell is recessive to brown shell, and bioluminescent body is dominant. You cross a neon, non-bioluminescent snail with a homozygous brown, bioluminescent snail. The F1 are then crossed with neon, non-bioluminescent snails (a testcross).
What ratios of offspring would you expect if loci for shell and body bioluminescent are:
- Linked with no crossing over?
- Sort independently?
- Linked but 18mu apart?