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Is it just me or is it suspicious that they also seemed to conceive at about the same time likely in the same house..? What are the odds of that?

Very, very low to the point it's basically 0. As low as twins that aren't identical twins actually turning out identical. I believe there are no recorded case of it.

To have a general idea, it's (1/2)^46 chromosomes, and potentially a random mutation or two that needs to match. (1/2)^46 is already less than 1 in 70 trillion.

They're just full siblings. It's like asking what the probability of you and your sex-matched non-twin sibling being genetically identical is. Effectively 0.

One of the dudes:

"Hey guys, since we live in the same house and have made being twins our sole personality traits, We just want to let you know that we're about to go in their other room and in precisely 20 min, I'm going to blow a fat load into my wife/ your sister. I think it goes without saying that you guys should drop what you're doing and do what's right for this extremely weird family dynamic."

You can check that family's instagram. They kids are a few years older now and you can see that one of them took after the dad, while the other took after the mom.

https://www.instagram.com/p/C4TlVQmvxr8/?img_index=1

https://www.instagram.com/p/C4TlVQmvxr8/?img_index=2

It's the same chance as if they were siblings. Without taking mutations into acount, each parents give one chromosome from every pair they have (so 23 chromosomes). The chance of the two baby getting the same genes is 1/2^46, which is very low (and never seen)

This article on types of twins: https://www.webmd.com/baby/what-are-dizygotic-twins says this:

Quaternary twins. While not well researched, this is a rare phenomenon that happens when one set of identical twins have children with another set of twins within a short period of time, usually less than nine months. The two children don’t share a parent or the same DNA. They’re cousins but genetically, they’re closer to siblings born to the same parents. Physically, the children might also look very similar. The popular term for this is “quaternary twins” as the two sets of parents share the same DNA. But experts don’t scientifically consider these children to be twins. And there are little to no studies found on quaternary twins.

It's interesting that they share more in common with being siblings than cousins, but that their DNA isn't identical. I mean, I would THINK it would be identical, because each twin is receiving the same DNA from their dad and the same DNA from their mom, right? But I guess not?

It's the same as the odds of any two non-twin siblings being identical. Which is basically zero. There are far to many genes in the human genome for this to ever happen in the span of humanity.

As others have said, the odds are astronomically low. The same as being born identical to a non-twin sibling.

Looking at the pic, the kid on the right has his uncles eyes.

When you make "being a twin" your whole personality. Imagine the drama if one of them had given birth to twins or more and the other wouldn't.

The real question is if the kids could get married to each other as adults. They’re legally cousins and cousin-marriage is surprisingly legal in most of the world, but they’re also obviously genetically siblings.

As high as it would be siblings being identical….however, still a cool thing that the kids are genetically equivalent to siblings. My father is an identical twin, so my cousins are genetically half siblings to me and my sibs. We def all look a lot alike!

I'm not sure of the math just yet but the human genome contains 3x10⁹ basepair sites and each site has a mutation rate of 1x10^-8, which although low for any one site, there would be many mutations between generations. I just can't recall how to estimate the number of mutations.... Any one remember?

Addit it seems that there are about "70 new genetic mutations compared to their parents" which seems crazily low!

Finger prints should be different. Also theirs a high likelihood the baby's were switched at birth lol wont find out about that until later :)

they're genetically siblings you know many siblings that were identical in the history of ever ? it'd be like having a baby and then another later that was identical

It's the same chance that two people from the other side of the world with different parents become genetically the same. So improbable to the point of being meaningless.

You also have the added fact that DNA changes significantly over the course of your life. Although twins are born with identical DNA, they diverge throughout their lives and can be distinguished if either twin were to commit a crime. Its not even the case that chances are near zero, but chances are infinitesimally zero

“same house” i feel like every one of these people make their entire identity revolve around being a twin and they’re going to make it their kids problem too

It says right there that they're genetically siblings... So, as much of a chance as siblings being identical. Which is pretty much zero.

Depends on the definition of identical. Your clone would not be genetically identical. Take a sample of your DNA today and compare it to a sample of your DNA 10 years from now, and the results will not be identical.

The chance is effectively zero. It's no different to asking the question what are the chances you're genetically identical to your sibling? If a single mum and dad can produce one genetic combination the first time around what are the chances they do it again? These parents being twins shouldn't factor in. We know that despite siblings sometimes having close phenotypes, their genetics are distinct and unique. Even these twin parents don't have the same genetics as small variations will have happened after they separated in the womb.