Identical Twins Are Not So Identical, Study Suggests (theguardian.com) 26
An anonymous reader quotes a report from The Guardian: Genetic differences between identical twins can begin very early in embryonic development, according to a study that researchers say has implications for examining the effects of nature versus nurture. Identical -- or monozygotic -- twins come from a single fertilized egg that splits in two. They are important research subjects because they are thought to have minimal genetic differences. This means that when physical or behavioral differences emerge, environmental factors are presumed to be the likely cause. But the new research, published on Thursday in the journal Nature Genetics, suggests the role of genetic factors in shaping these differences has been underestimated.
[Kari Stefansson, the co-author of the paper and head of Iceland's deCODE genetics] and his team sequenced the genomes of 387 pairs of identical twins and their parents, spouses and children in order to track genetic mutations. They measured mutations that occurred during embryonic growth and found that identical twins differed by an average of 5.2 early developmental mutations. In 15% of twins, the number of diverging mutations was higher. When a mutation happened in the first few weeks of embryonic development, it would be expected to be widespread both in an individual's cells and in those of their offspring.
In one of the pairs of twins studied, for example, a mutation was present in all cells in one sibling's body -- meaning it is likely to have happened very early in development -- but not at all in the other twin. Stefansson said that out of the initial mass that would go on to form the individuals, "one of the twins is made out of the descendants of the cell where the mutation took place and nothing else," while the other was not. "These mutations are interesting because they allow you to begin to explore the way in which twinning happens."
[Kari Stefansson, the co-author of the paper and head of Iceland's deCODE genetics] and his team sequenced the genomes of 387 pairs of identical twins and their parents, spouses and children in order to track genetic mutations. They measured mutations that occurred during embryonic growth and found that identical twins differed by an average of 5.2 early developmental mutations. In 15% of twins, the number of diverging mutations was higher. When a mutation happened in the first few weeks of embryonic development, it would be expected to be widespread both in an individual's cells and in those of their offspring.
In one of the pairs of twins studied, for example, a mutation was present in all cells in one sibling's body -- meaning it is likely to have happened very early in development -- but not at all in the other twin. Stefansson said that out of the initial mass that would go on to form the individuals, "one of the twins is made out of the descendants of the cell where the mutation took place and nothing else," while the other was not. "These mutations are interesting because they allow you to begin to explore the way in which twinning happens."
That means humping my twin is not masturbation (Score:4, Funny)
which is a relief because my faith forbids masturbation.
the family that lays together stays together (Score:2, Informative)
Re: (Score:3)
Re: (Score:3)
I think you will have to explain to him why you consider yourself a superior option to his aforementioned twin.
Re: That means humping my twin is not masturbation (Score:2)
Donuts (Score:2)
It would have been an easier read if they just have said twins are made from a donut and a donuthole.
Re: (Score:2)
A riddle for foreigners ... (Score:2)
Why do Americans eat baked goods filled with a hole, when they could have baked goods filled with nutella or steak and beer gravy?
Re: (Score:2)
I assume you are trying to be funny, but the donut shape minimizes the distance from the surface to any interior point for a given volume while still providing a shape that can be floated stably on both sides. The shape is entirely for cooking purposes.
The rate of mutation is fascinating to me. (Score:2)
I always assumed, mutation would happnen more on geological time scales. Species changing over millions of years.
But this, and the mutation rates of Covid, clearly suggests a really fast mutation rate.
And also a, at least to me, surprising resilience.
And both sound like very useful things to exploit!
TL;DR: Can I have my over-the-counter aesthetic skin modification gene therapy pills now? Grow some wings too. Eagle eyes would be nice too. Oh, and immunity to the power of both Covid and stupid would be super-
Re: The rate of mutation is fascinating to me. (Score:2)
Mutations happen in different parts of the genome at different rate. There are papers on muti-fractal analysis of genomes that reveal this though I do not fully understand the mechanism. I think it's related to the tertiary structure, like protein folds but not sure and not my expertise.
So the genome has a built in security structure to some degree and in somethings like virus, there is likely more room for mutability.
Re: (Score:2)
But this, and the mutation rates of Covid, clearly suggests a really fast mutation rate.
Bacteria and viruses mutate fast purely because their generations are so short, not because they have spacial powers. When you look at evolutionary adaptation, this fast mutation rate makes up for their lack of sexual reproduction, which is the big driver for adaptation in larger creatures.
Re: (Score:2)
Mutations happen all the time. Cells have mechanisms in place to correct the mutations, but sometimes those mechanisms fail. When they fail, often the mutated cell isn't viable and dies. Unfortunately, it also results in cancer. Cancer is a disease of the genome.
obligatory hhgttg quote (Score:1)
The Haggunennons of Vicissitus Three have the most impatient chromosomes of any life-forms in the galaxy. Where as most races are content to evolve slowly and carefully over thousands of generations - discarding a prehensile toe here, nervously hazarding another nostril there, the Haggunennons would do for Charles Darwin what a squadron of Arcturan Stunt-Apples would have done for Sir Isaac Newton. Their genetic structure, based on the quadruple-striated octo-helix, is so chronically unstable, that far from
Kári is sort of Iceland's Elon Musk (Score:2)
Brilliant guy, achieved a lot that others said was impossible**, and also says whatever the heck he wants, even if it frequently gets him in trouble. ;) Really glad we have him, though. His company, DeCODE, and his strong advocacy for integrating their capabilities into the government response, proved essential for us having such an effective COVID response (no thanks to the incompetent management at Landakot, whose carelessness resulted in the majority of our deaths in a single incident). Also thanks to
Re: (Score:2)
So Iceland's famed genealogy database was his idea?
Having an entire country sequenced is a priceless resource in correlating diseases with genetics. Given that the whole idea of human genetics is anathema to the Woke, would such a project even be possible anywhere else?
known they're not truly "identical" (Score:2)
Many unique traits aren't specified in DNA, for example 'identitical' twins don't have the same fingerprints, though they are similar.
Re: (Score:2)
We know (Score:2)
They even have different first-names.
Re: (Score:1)
Don and Boris
Re: (Score:2)
I think Jeremy Corbyn is more our rabble-rousing populist who got booted out but won't leave.
Boris is just a bumbling posh cunt.
Re: (Score:1)
But, but, the screwy hair thing
Re: (Score:2)
A good point, that somehow escaped the so-called scientist who wrote the report, but unfortunately you are not 100% accurate:
https://eu.jsonline.com/story/... [jsonline.com]