Telomeres and chromosome loss in hybridomas
In my reading about the formation of hybrids between human fibroblasts or
lymphocytes and mouse tumor cell lines, I encounter little in the way of
explanation for the unequal chromosome loss in the hybrid cells. I
recognize that it is advantageous for mapping genes to human chromosomes
that most (but not all) of the human chromosomes are lost, but my
question is why are the human chromosomes lost and not those of the mouse?
I only know of the following two speculations:
1) Mouse chromosomes may replicate more quickly than human chromosomes.
Failure to replicate as quickly results in loss.
2) The chromosome loss happens in a similar way as occurs in haploidization
in Aspergillis. I'm not sure why or how this would account for the species
bias of chromosome loss, but it was mentioned by one author.
Does anyone know of work examining how differences in telomeres and
telomerase in the two parent cell lines might contribute to the differential
chromosome loss?
Have reciprocal fusions been made in which human tumor lines have been fused
with mouse fibroblasts or lymphocytes? Are mouse chromosomes lost in such
hybrids?
Thank you.
