In another advance, the researchers fired an electron beam at a tiny 3D crystal and generated its molecular structure in minutes.
Also, the researchers are applying the techniques to study how human cells mature over a lifetime, how tissues regenerate, and how cells change in diseases including cancer, according to Pennisi.
The researchers isolate whole cells from organisms, sequence their genomic contents in what is known as single-cell RNA-seq, and tag early cells and their descendants in order to track how they split into multiple types during development.
Jeremy Berg, Science's editor-in-chief, said the rich information about cell type inventories would lay the foundation for future studies of developmental processes, providing insights into the seemingly miraculous transformation of single cells into complex organisms.
Studies on molecular level resulted in five breakthroughs in 2018: fat molecules revealed the oldest animal on Earth; a DNA analysis of a bone fragment more than 100,000 years ago proved it a hybrid between Neanderthal and Denisovan; proteins within a cell worked by condensing into separated liquid droplets; a DNA database comparison helped police nab cold killers; the first gene-silencing drugs got approved.
"These technologies create some of the most extraordinary movies ever made, showing how a single cell grows into the intricate tissues and organs of a mature animal," said Tim Appenzeller, Science's news editor.
Among runners-up to the ten breakthroughs are the neutrino as a messenger from a far-off galaxy. A neutrino collided with massive detector under the South Pole ice proved to come from a blazar four billion light years away.
Also, an asteroid slamming into Greenland, perhaps 13,000 years ago may cool down the Earth for about 1,000 years as the planet is wrapping up its Ice Age.
"In 2018 alone, studies detailed how a flatworm, a fish, a frog, and other organisms begin to make organs and appendages," said Science staff writer Elizabeth Pennisi.
WASHINGTON, Dec. 20 (Xinhua) -- The single-cell analysis of gene activity through time were named on Thursday by the influential U.S. journal Science as 2018's Breakthrough of the Year.
What makes the three-step technique stronger is the use of molecular "trackers." The researchers have introduced fluorescent tags or the gene editing technique CRISPR, Science's 2015 Breakthrough of the Year, into early embryonic cells to mark them.
The RNA sequencing technology is enabling researchers to determine, at the individual cell level, which genes are turned on and off as an early embryo develops.
An unusual inclusion in this year's list is the campaign against sexual harassment in the science community. Some institutions took action to tackle the issue with some famed scientists fired or forced out because of sexual scandals. Advocacy groups say actions taken thus far are inadequate.
It could transform the basic biology and medical research landscape in the next ten years, according to Science.