Grant Morahan (morahan at wehi.edu.au) wrote:
: Hello,
: We have been analysing genetic susceptibility to an experimentally-induced
: disease in mice. The results are surprising.
: Inbred strain A -100% susceptible;
: inbred strain B -100% resistant.
: (AxB)F1 - 50% are susceptible.
: F2 - 25% are susceptible. So far, so good.
: But 50% of the ((AxB)xA)BC1 mice develop disease.
: (We don't have results for the reciprocal BC yet).
: The problem is that the BC doesn't seem more susceptible than the F1.
: Can anyone suggest a genetic model to explain these results? We haven't
: been able to come up with one.
: Any suggestions would be welcome.
: -Grant
: --
: Grant Morahan, Ph.D.
: The Walter and Eliza Hall Institute of Medical Research
: Parkville, Victoria
: AUSTRALIA
Hi,
I am not big expert in genetics, I just recently got into this field. What
really makes me worry is your 50% in F1. By the book this has only a few
explanations
x-linked (that would actually work nicely, but cannot explain the 25% F2)
otherwise sex linked (mitochondrial DNA, MMTV)
non-genetic reasons i.e. e.g. environmental, age
Otherwise is it possible that the parental strains are not homozygous?
Hope this might help
Ulrich Beutner
Ubeutner at isrec.unil.c
