What you call “twiblings” does happen rarely in nature: it is called polar-body twins or half-identical or semi-identical twins. Only two occurrences are known to have happened in humans (I am sure it has happened other times): Semi-identical twins ‘identified for only the second time’ - BBC News
Apparently the scientific name for this is “Sesquizygotic Twinning”.
There’s a great video explanation of this process. I’m still not entirely clear on how the maternal set of chromosomes replicates itself such that it can form diploid cell lines with both sperm. Usually the sperm and egg chromosomes pair up after merging of the pronucleus of each. The authors of the paper you linked propose some strange “triploid spindle apparatus” as an explanation of how this happens. But it’s not clear to me how the chromosomes of each haploid pronucleus replicate before joining with their counterparts. And I’m too lazy to try to figure it out right now.
What you call “twiblings” does happen rarely in nature: it is called polar-body twins or half-identical or semi-identical twins. Only two occurrences are known to have happened in humans (I am sure it has happened other times): Semi-identical twins ‘identified for only the second time’ - BBC News
Here is the paper in NEJM: Molecular Support for Heterogonesis Resulting in Sesquizygotic Twinning | NEJM
Wow, very interesting! Thanks for sharing.
Apparently the scientific name for this is “Sesquizygotic Twinning”.
There’s a great video explanation of this process. I’m still not entirely clear on how the maternal set of chromosomes replicates itself such that it can form diploid cell lines with both sperm. Usually the sperm and egg chromosomes pair up after merging of the pronucleus of each. The authors of the paper you linked propose some strange “triploid spindle apparatus” as an explanation of how this happens. But it’s not clear to me how the chromosomes of each haploid pronucleus replicate before joining with their counterparts. And I’m too lazy to try to figure it out right now.