In addition to Genetic Counseling for the cards, your lab has been investigating the genetics of the Dormouse.
Dormice have either the ability to Speak (S) – or are Mute(s).
Additionally, they are either Cruel or Kind.
You wish to map the distance between the Speech and Disposition genes and determine whether Cruelty or Kindness is dominant. (Here, not a metaphysical question)
You begin by obtaining true-breeding animals:
- A Speaking , Kind Male
- A Mute, Cruel Female
(oh, the cries of misogyny!)
Once bred, this coupling gives rise to a litter of six offspring. All six can speak and are unfailingly kind.
These offspring are then bred to true-breeding homozygous recessive mates. The results of these matings are:
35 Speaking, Kind
15 Speaking, Cruel
15 Mute, Kind
35 Mute, Cruel
- What can you determine from these results?
In similar experiments, Cruel, Longhair and Kind,Shorthair animals were examined. Both parentals were true breeding and the F1 litter consistend entirely of Kind, Longhair animals. These F1 were then crossed with homoztgous recessives for both traits, resulting in:
20 Kind, Longhair
80 Kind, Shorthair
80 Cruel, Longhair
20 Cruel, Shorthair
What do these data add to your understanding of Dormouse genetics? Can you map the three genes to one Chromosome? What experiment do you want to do next?