Posted on 02/28/2019 4:04:42 PM PST by EveningStar
Boy and girl, now four, are only the second case of ‘sesquizygotic’ twins recorded
A pair of twins have stunned researchers after it emerged that they are neither identical nor fraternal – but something in between.
The team say the boy and girl, now four years old, are the second case of semi-identical twins ever recorded, and the first to be spotted while the mother was pregnant.
The situation was a surprise to the researchers. An ultrasound of the 28-year old mother at six weeks suggested the twins were identical – with signs including a shared placenta. But it soon became clear all was not as it seemed.
(Excerpt) Read more at theguardian.com ...
Wow, I didn’t know that an unfertized human egg could split into two before it was fertilized. Still learning something new every day.
Waiting for pics of John kasich and Mitt Romney.
did not read the article, but did it say the ovum split before fertilization?
That is weird.
ditto to the last part of your post.
Caused by global warming?
(from article)
“Twins are normally either identical or fraternal. In the case of identical, one egg is fertilised by one sperm, but the resulting ball of cells splits in two, giving rise to two offspring with identical genetic material. In the case of fraternal, or non-identical, twins, two eggs are fertilised, each by a different sperm. The resulting siblings arise from the same pregnancy, but are no more genetically similar than siblings from the same parents born at a different time.”
SO.... one egg splits in two - Identical twins
Two eggs fertilized at same time by different sperm - Fraternal twins
Three sperm fertilize the same egg - semi-identical twins
I have heard of the ovum splitting before fertilization which can then become fertilied by two different sperm.
Seems that I heard it a long time ago, too.
that is not supposed to be possible; yet there is living proof that it can happen. Wow.
I’m hearing the voice of Rush Limbaugh saying “It means; She’s a Slut!” Remember the Sandra Fluke dramas of 2011?
He lost a lot of advertisers for that amusing remark.
“An ultrasound of the 28-year old mother at six weeks suggested the twins were identical...”
At only six weeks they can tell this? From my old science books I thought they were still “fish” with “gill slits” at that stage.
It’s only until they are born that you are certain it was a human in there. /s
BTW - we have identical twins, but never had them tested as such. (It was obvious, and no real need to.) I’m guessing that a lot of (most?) twins never get tested, so perhaps this is more common than they think??
Very interesting. Until recently, it would just have been assumed that any such cases were fraternal twins.
The article said that they looked at around 1,000 sets of genetic data from twins and didn’t find any others like this. That would indicate it’s pretty rare.
An ultrasound at six weeks is unusual in my experience. 15 weeks was more typical. I wonder if there were indications that something was wrong.
A single placenta and single amniotic sac with two embryos, indicate identical twins. Two amniotic sacs with an embryo in each indicates fraternal.
And just so everyone knows so you can argue with your Lib friends, babies are fully formed by 12 weeks gestation. From there on out, they simply grow. And there is a detectable heartbeat at 18 days gestation. Use those facts the next time your Lib friends refer to a baby in the womb as ‘just a clump of cells’.
No it was fertilized by two sperm and then split.
If you REALLY want to learn something, read the article!
Don’t believe posts from those to that are too lazy to read the artcle.
I think that the twins are not optimal specimens of humans.
Baby girl and blood clot and lost arm then had ovaries removed because they were sub optimal.
Have no idea of cognitive ability.
This is very unusual, and it would likely have a negative impact on reproductive organs. The blood clot might have just come up.
did not read the article, but did it say the ovum split before fertilization?
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No, it had some other “explanation” that appeared (to me) to be nonsense.
The twins that the article discussed each had their cells with nuclei that contained genetic material that consisted of IDENTICAL haploid genetic material from the mother. As best as I remember from freshman biology, the haploid (the genetic material in the egg) of each egg produced by the mother contains a unique combination of the mother’s thousands of genes/genetic material. In other words, the maternal haploid contribution in both twins must have originated from a single egg. Once that maternal haploid “combines” with the haploid from a sperm, it’s no longer a haploid but complete (46 chromosomes) genetic material for the now fertilized egg. The maternal haploid is no longer available to “combine” with the haploid of a different sperm. So, the maternal haploid must have somehow split into two absolutely identical maternal haploids to be available for two different sperm.
My curiosity is aroused so I’m going to have to look into this more.
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