The fusion of embryonic cells into the mother is the norm, and yes is a specific form of mosaicism, but isn’t usually specified as such (as it’s normal anyway).
The mosaic genetic variance from single zygote is usually single sex, but not always (46XY/46XX where a single ovum has been fertilised by two sperm, but 46XY/46X. or 46XX/46XX(sry) are also possible by loss of genetic material - the latter being exceptionally rare).
It’s quite difficult to prove chimera - distinguishing it from double fertilisation is a problem, particularly distinguishing whether genetic separation occurred before or during the first division, or if the ovum split and two separate fertilisations occurred, in which case the result is still usually referred to as mosaicism. The only case where it’s reasonable to make a distinction to chimerism is when 4 stable allele variants are present for a single gene and not cross mixed; also, to be certain, it requires this to occur in many genes, so indicating that two fully stable zygotes have fused. It’s also very rare.
I also specified ‘true chimera’, the ‘true’ bit is the bit that specifies different species - this can occur in cats as many cat species will form viable hybrids.
I’ve been trying to work out how to respond to this, so…
I think you may well know of one or two aspects my personal interest in this (I’ve written about two of them) or you may just be aware that I have an interest in this - I suspect the latter. However, there’s actually quite a bit more that isn’t known here, including a possible mosaicism (which I’m really not going to discuss on an open forum).
That didn’t really clarify, did it? I am aware of some of your interests, which you have mentioned here. I have some knowledge in some of those fields (we ‘covered’ things like this at Liverpool Uni where I did Life Sciences, and I came across some aspects of this while doing my PhD in Edinburgh, though it had nothing to do with my thesis.
BREAKING:
In an effort to win the constructor’s title, the Ferrari F1 team fired their entire pit crew yesterday and replaced them with just four scousers. This announcement follows a recent documentary showing how unemployed youths from Toxteth were able to remove a set of wheels in less than 6 seconds without proper equipment, whereas Ferrari’s crew could only do it in 8 seconds with millions of pounds worth of high-tech equipment. It was thought to be a bold move by the Ferrari management as most races are won and lost in the pits. However, Ferrari got more than they bargained for!
At the crew’s first practice session, not only was the scouse pit crew able to change all four wheels in under 6 seconds but, within 12 seconds, they had re-sprayed, re-badged and sold the car to the Mercedes team for 8 cases of Stella, a bag of weed and some photos of Hamilton’s ex-bird in the shower.
) to deep dive this particular aspect of biology!
