冰岛大学Kari Stefansson、Daniel F. Gudbjartsson等研究人员合作揭示单卵双胞胎生殖系基因组之间的差异。相关论文发表在2021年1月7日出版的《自然—遗传学》杂志上。
Title: Differences between germline genomes of monozygotic twins
Author: Hakon Jonsson, Erna Magnusdottir, Hannes P. Eggertsson, Olafur A. Stefansson, Gudny A. Arnadottir, Ogmundur Eiriksson, Florian Zink, Einar A. Helgason, Ingileif Jonsdottir, Arnaldur Gylfason, Adalbjorg Jonasdottir, Aslaug Jonasdottir, Doruk Beyter, Thora Steingrimsdottir, Gudmundur L. Norddahl, Olafur Th. Magnusson, Gisli Masson, Bjarni V. Halldorsson, Unnur Thorsteinsdottir, Agnar Helgason, Patrick Sulem, Daniel F. Gudbjartsson, Kari Stefansson
Abstract: Despite the important role that monozygotic twins have played in genetics research, little is known about their genomic differences. Here we show that monozygotic twins differ on average by 5.2 early developmental mutations and that approximately 15% of monozygotic twins have a substantial number of these early developmental mutations specific to one of them. Using the parents and offspring of twins, we identified pre-twinning mutations. We observed instances where a twin was formed from a single cell lineage in the pre-twinning cell mass and instances where a twin was formed from several cell lineages. CpG>TpG mutations increased in frequency with embryonic development, coinciding with an increase in DNA methylation. Our results indicate that allocations of cells during development shapes genomic differences between monozygotic twins. Whole-genome sequencing of monozygotic twins, along with their parents, spouses and children, identifies postzygotic mutations present in the somatic tissue of one twin, but not the other, and characterizes differences in the number and timing of these mutations.