Sorry to butt in but I nicked this article on epigenetics from Fertility Friends and thought it would be of interest to Choco, Tame and anyone else who may decide to opt for donor eggs in the future:
"...Remembering that 99.9% of a baby?s genes are identical to all other humans, 0.1% results in the variations we see in humans.
A baby conceived using a donor egg (roughly the size of a full stop) gets his/her genes from the donor; she gets the 'instructions' on the expression of those genes from the woman who carries him/her to term.
This means that a baby conceived using donor egg has 3 biological parents: a father, the egg donor and the woman that carries the pregnancy. The child who is born would have been physically & no doubt emotionally different had another woman carried that child. In other words the birth mother influences what the child is like at a genetic level ? it IS her child. She has had a 'say' in her offspring as does the donated egg and the sperm used to fertilized.
In horse breeding for example, it?s not uncommon to implant a pony embryo into the womb of a horse. The foals that result are different from normal ponies. They?re bigger. These animals? genotype ? their genes ? are the same as a pony?s, but their phenotype ? what their genes actually look like in the living animal ? is different. Taken from a booklet published by Freedom Pharmacy ?Perhaps the greatest myth surrounds pregnancy. Many believe the uterus is simply an incubator. Nothing could be further from the truth.
The most important aspect of all pregnancies ? including egg donation pregnancies - is that as the fetus grows, every cell in the developing body is built out of the pregnant mother?s body. Tissue from her uterine lining will contribute to the formation of the placenta, which will link her child. The fetus will use her body?s protein, then she will replace it. The fetus uses her sugar's calcium, nitrates, and fluids, and she will replace them. So, if you think of your dream as you dream house, the genes provide merely a basic blueprint, the biological mother takes care of all the materials and construction, from the foundation right on up to the light fixtures. So, although her husband?s aunt Sara or the donor?s grandfather may have genetically programmed the shape of the new baby?s earlobe, the earlobe itself is the pregnant woman?s 'flesh and blood'. That means the earlobe, along with the baby herself, grew from the recipient?s body. That is why the child is her biological child...?