In the following website, a geneticist says “… you can’t make a zygote by fusing two eggs or adding one egg’s DNA to another’s. This is even though the resulting embryo would have the usual 46 chromosomes.
The reason isn’t some special string of A’s, G’s, T’s or C’s found in dad’s DNA. No, instead it has to do with chemical marks found on egg and sperm DNA. This methylation (as the marks are called) makes the DNA from each parent unique and you need both to form a zygote.
What these marks do is affect how at least 80 different genes are used. In science speak, **these genes are imprinted**.”, link; [https://genetics.thetech.org/node/750](https://genetics.thetech.org/node/750)
It seems according to geneticists, Genomic imprinting is the **only** reason an egg can not fuse with another egg to form a zygote; but this has brought up more questions I need answers to.
My questions are; 1) if Genomic imprinting is the only thing that stops an egg from fusing with another egg to form a zygote, would this mean there is nothing to stop an egg from fusing with another egg and forming a zygote in species that lack Genomic imprinting?
2) But if in species that lack Genomic imprinting, an egg can never fuse with another egg to form a zygote, that would mean Genomic imprinting is not the only reason an egg can not fuse with another egg, right?
3) Or is it that species that lack Genomic imprinting have analogous processes similar to Genomic imprinting that have helped and help decipher the mechanisms of specific gene expression which stop an egg from fusing with another egg and forming a zygote?
4) Hypothetically speaking, would an egg “fusing” with another egg mean this egg is “fertilizing” another egg? And is this “sexual reproduction”?
In: Biology
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