Sep 29, 2021 03:17 AM
All Identical Twins Appear to Carry a Hidden Chemical Signature on Their DNA
https://www.sciencealert.com/all-identic...-their-dna
INTRO: Identical twins originate from one egg cell that splits and gives rise to two embryos, but during development, one twin sometimes "vanishes", leaving only one baby to be born. Now, a new study hints that your DNA may reveal whether you started out as an identical twin in the womb, even if your twin disappeared long before your birth.
In the new study, published Tuesday (Sept. 28) in the journal Nature Communications, the researchers zoomed in on so-called epigenetic modifications found in twin DNA. The term "epigenetic" refers to factors that can switch genes "on" or "off" without changing their underlying DNA sequence. For example, small molecules called methyl groups can cling like sticky notes to specific genes and prevent the cell from reading those genes, thus effectively switching them off.
According to the new study, the DNA of identical twins comes adorned with a characteristic pattern of sticky methyl groups. This pattern spans 834 genes and can be used to differentiate identical twins from both fraternal twins and non-twins, the authors found. And, in fact, based on these results, the team developed a computer algorithm that can reliably identify an identical twin based solely on the location of methyl groups across their DNA.
In theory, such a tool would also be able to spot someone who'd had a vanishing twin, although the new study didn't test this idea... (MORE)
https://www.sciencealert.com/all-identic...-their-dna
INTRO: Identical twins originate from one egg cell that splits and gives rise to two embryos, but during development, one twin sometimes "vanishes", leaving only one baby to be born. Now, a new study hints that your DNA may reveal whether you started out as an identical twin in the womb, even if your twin disappeared long before your birth.
In the new study, published Tuesday (Sept. 28) in the journal Nature Communications, the researchers zoomed in on so-called epigenetic modifications found in twin DNA. The term "epigenetic" refers to factors that can switch genes "on" or "off" without changing their underlying DNA sequence. For example, small molecules called methyl groups can cling like sticky notes to specific genes and prevent the cell from reading those genes, thus effectively switching them off.
According to the new study, the DNA of identical twins comes adorned with a characteristic pattern of sticky methyl groups. This pattern spans 834 genes and can be used to differentiate identical twins from both fraternal twins and non-twins, the authors found. And, in fact, based on these results, the team developed a computer algorithm that can reliably identify an identical twin based solely on the location of methyl groups across their DNA.
In theory, such a tool would also be able to spot someone who'd had a vanishing twin, although the new study didn't test this idea... (MORE)