deCODE genetics: Monozygous but not identical
PR87490
REYKJAVIK, Iceland, January 7, 2021, /PRNewswire=KYODO JBN/--
By sequencing the germline genomes of twins and comparing them to those of
close relatives, scientists at deCODE genetics found mutations that are present
in just one of the monozygotic twins and traced them back to the first days
after conception.
In the article, Differences between germline genomes of monozygotic twins,
published in Nature Genetics today scientists at deCODE genetics searched for
mutations that were present in only one of monozygotic twins.
In the study of human genetics the genomes of monozygotic twins are often
assumed to be identical, and differences between them have been pinned on the
environment rather than genetics. This assumption has been used throughout the
centuries to disentangle the contribution of genetics and environment to
disease and other phenotypes.
The scientists found two groups of twin pairs, one where twins share mutations
and another where the developmental mutations are only present in one of them
at high frequency.
"Mutations can be formed when cells divide and the daughter cells may carry a
mutation that marks the descendants of the mutated cell within an individual.
Mutations that are present in only one of the twins allow us therefore to
backtrack to the cell divisions that lead to the development of the twins."
says Hákon Jónsson scientist at deCODE Genetics and author on the paper.
Remarkably this backtracking of the mutations that differ between twins
suggests that the mutations are formed in the first days of embryonic
development when the embryo consists of several cells.
"These two groups of monozygotic twins give insight into development of the
embryo only few divisions after conception when the embryo consists of several
cells," says Kari Stefansson CEO of deCODE genetics. "These are exciting times
that allows us to use mutations to shed light on the development of humans at
these first stages of development."
Hákon Jónsson and colleagues sequenced the genomes of 387 pairs of identical
twins and their parents, spouses and children to track mutation divergence. The
authors found that twins differ by 5.2 early developmental mutations, on
average. In approximately 15% of twin pairs, one twin carries a high number of
these mutations that the other twin does not have.
Physical or behavioral differences between identical twins are usually
attributed to environmental factors, according to the assumption that genetic
differences between the pair are minimal. However, autism and other
developmental disorders—which one twin in a pair might have—are linked to
genetic mutations. The authors conclude that the role of genetic factors in
shaping such phenotypic differences has been underestimated.
Thora Kristin Asgeirsdottir, PR and Communications deCODE genetics, 00354 -570
1909, 00354 -894 1909, thoraa@decode.is
Photo - https://mma.prnewswire.com/media/1395021/deCODE_twins.jpg
SOURCE: deCODE genetics Inc
本プレスリリースは発表元が入力した原稿をそのまま掲載しております。また、プレスリリースへのお問い合わせは発表元に直接お願いいたします。
このプレスリリースには、報道機関向けの情報があります。
プレス会員登録を行うと、広報担当者の連絡先や、イベント・記者会見の情報など、報道機関だけに公開する情報が閲覧できるようになります。