https://www.reuters.com/article/us-health-reproduction-mosaic-twins/doctors-confirm-new-type-of-twin-born-from-one-egg-and-two-sperm-idUSKCN1QG2YH

(Reuters Health) – Doctors in Australia say they have identified a second case of twins apparently created from one egg and two sperm, a boy-girl combination in whom the mother’s DNA is identical in both babies but the father’s DNA varies in each twin.

They’re being called semi-identical twins and a new study in the New England Journal of Medicine suggests that such twins are extraordinarily rare. The only other reported case was uncovered in 2007.

Virtually all twins are either fraternal (where two eggs and two sperm have created two separate embryos) or identical (where one embryo splits in two before resuming normal development for each child).

“This is confirming there is this third type of twinning where it’s not fraternal and it’s not identical. It’s this strange place in between,” chief author Dr. Michael Terrence Gabbett of Queensland University of Technology in Brisbane told Reuters Health in a telephone interview.

—-

The ABC article said that this type of fertilisation can occur but the embryos usually self-aborted.

I imagine these twins will be studied in detail over the years.

Read an article about this in yesterday’s Graun. I had to go through it three times before I really understood what happened. Biology is not my strong suit.

sesquizygotic twins

—

Yes, interesting.

>>Doctors in Australia say they have identified a second case of twins apparently created from one egg and two sperm, a boy-girl combination in whom the mother’s DNA is identical in both babies but the father’s DNA varies in each twin.

I don’t get this bit.

Peak Warming Man said:

>>Doctors in Australia say they have identified a second case of twins apparently created from one egg and two sperm, a boy-girl combination in whom the mother’s DNA is identical in both babies but the father’s DNA varies in each twin.

I don’t get this bit.

https://www.theguardian.com/science/2019/feb/27/scientists-stunned-discovery-semi-identical-twins

That article has some pictures which explain it.

Does this mean that it’s possible for twins to have different fathers?

Lary said:

Does this mean that it’s possible for twins to have different fathers?

Yes.
https://en.m.wikipedia.org/wiki/Superfecundation

sibeen said:

Peak Warming Man said:

>>Doctors in Australia say they have identified a second case of twins apparently created from one egg and two sperm, a boy-girl combination in whom the mother’s DNA is identical in both babies but the father’s DNA varies in each twin.

I don’t get this bit.

https://www.theguardian.com/science/2019/feb/27/scientists-stunned-discovery-semi-identical-twins

That article has some pictures which explain it.

Ta…I think.

Peak Warming Man said:

sibeen said:

Peak Warming Man said:

>>Doctors in Australia say they have identified a second case of twins apparently created from one egg and two sperm, a boy-girl combination in whom the mother’s DNA is identical in both babies but the father’s DNA varies in each twin.

I don’t get this bit.

https://www.theguardian.com/science/2019/feb/27/scientists-stunned-discovery-semi-identical-twins

That article has some pictures which explain it.

Ta…I think.

Took me a few go throughs :)

I think this could be very very exciting news for gay couples, if they can pull it off in the lab.

Rule 303 said:

I think this could be very very exciting news for gay couples, if they can pull it off in the lab.

Or close to the lab, it has to be still warm.

Rule 303 said:

I think this could be very very exciting news for gay couples, if they can pull it off in the lab.

As the fertilised egg divided and the ball of cells grew, those containing only chromosomes from the two sperm died.

Divine Angel said:

Lary said:

Does this mean that it’s possible for twins to have different fathers?

Yes.
https://en.m.wikipedia.org/wiki/Superfecundation

Even without this semi-identical business, it was possible for twins to have different fathers (fraternal twins, cause by separate fertilisation events.)

Divine Angel said:

Lary said:

Does this mean that it’s possible for twins to have different fathers?

Yes.
https://en.m.wikipedia.org/wiki/Superfecundation

That article in wikipedia doesn’t actually explain it. What it’s describing is actually semi-fraternal twins, not semi-identical twins. There’s a world of difference.

So, what are semi-identical twins and how often can they occur?

I should start more threads.

sarahs mum said:

I should start more threads.

*nods *

kii said:

sarahs mum said:

I should start more threads.

*nods *

Joins the nodding.

Yes, yes you should, sm.

mollwollfumble said:

Divine Angel said:

Lary said:

Does this mean that it’s possible for twins to have different fathers?

Yes.
https://en.m.wikipedia.org/wiki/Superfecundation

That article in wikipedia doesn’t actually explain it. What it’s describing is actually semi-fraternal twins, not semi-identical twins. There’s a world of difference.

So, what are semi-identical twins and how often can they occur?

“what are semi-identical twins”

Semi-identical twins are twins created from two sperm and one ovum.

“how often can they occur”

As mentioned above, the recent case is the second recorded case, ever, though of course there would be undetected cases.
Certainly seems as though it is something on the scale of one-in-a—few-billion kind of thing.

dv said:

mollwollfumble said:

Divine Angel said:

Yes.
https://en.m.wikipedia.org/wiki/Superfecundation

That article in wikipedia doesn’t actually explain it. What it’s describing is actually semi-fraternal twins, not semi-identical twins. There’s a world of difference.

So, what are semi-identical twins and how often can they occur?

“what are semi-identical twins”

Semi-identical twins are twins created from two sperm and one ovum.

“how often can they occur”

As mentioned above, the recent case is the second recorded case, ever, though of course there would be undetected cases.
Certainly seems as though it is something on the scale of one-in-a—few-billion kind of thing.

OKay. That is different.

I used to be a member of a group called Unique! Members are people with unique or extremely rare genetic disorders. There only ever have been and ever will be five people with my chromosomal rearrangement, all close relatives of me.

So I know a bit wbout unique genetics. There are some very strange variants out there.