An international group of researchers headed by scientists from the Vrije University Amsterdam (VU) has, for the first time ever, discovered a biological explanation of what causes identical twins.
The group, led by biological psychologist Jenny van Dongen and professor Dorret Boomsma of the VU, found that it is not the DNA of identical twins that they should be looking at. Rather, they discovered that there’s a certain substance that attaches itself to the DNA, The NOS reports.
Differently packaged DNA
The researchers discovered that the DNA of identical twins is “packaged” differently than that of other people. In a program on NPO Radio 1, Boomsma said that everyone has what is known as methyl groups attached to their DNA.
However, “It turns out that in more than 800 places in the DNA, the methylation is different in identical twins than in the rest of the population.” Boomsma added that this process probably starts very early after conception.
Quick biology lesson: identical twins occur when a single fertilized egg splits in two. Fraternal twins (A.K.A. non-identical ones) develop from two fertilized eggs. 👩👧👦
A mystery solved
According to Boomsma, “This is a very big discovery because the origin and birth of identical twins has always been a complete mystery.” 😱 This revelation is also important for research into birth defects.
More than 6,000 twins
In doing this research, the scientists looked at the DNA of more than 6,000 twins — using twin registries from the Netherlands, Great Britain, Finland, and Australia.
What are your thoughts on this groundbreaking discovery of the origin of identical twins? Tell us in the comments below!
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