First Gap-less Human Genome Sequence Published; Here's How the 2003 Work is Complete Now

Two decades after the Human Genome Project produced the first draft human genome sequence, scientists have published the first complete, gapless sequence of a human genome.

Analyses of the complete genome sequence will significantly add to our knowledge of chromosomes, including more accurate maps for five chromosome arms, which opens new lines of research, the National Human Genome Research Institute (NIH) said. This helps answer basic biology questions about how chromosomes properly segregate and divide, NIH added.

3 Billion Bases in DNA

The esearchers said that having a complete, gap-free sequence of the roughly 3 billion bases in our DNA is critical for understanding the full spectrum of human genomic variation. It also helps in the understanding of the genetic contributions to certain diseases.

"Generating a truly complete human genome sequence represents an incredible scientific achievement, providing the first comprehensive view of our DNA blueprint ... This foundational information will strengthen the many ongoing efforts to understand all the functional nuances of the human genome, which in turn will empower genetic studies of human disease," said Eric Green, director of National Human Genome Research Institute (NHGRI).

Though researchers unveiled a complete sequence of the human genome back in 2003, some 8 percent of it had not been fully deciphered. Now, a consortium of scientists have resolved the gap in the research.

A DNA double helix is seen in an undated artist's illustration released by the National Human Genome Research Institute to Reuters on May 15, 2012. A group of 25 scientists June 2, 2016, proposed an ambitious project to create a synthetic human genome, or genetic blueprint, in an endeavor that is bound to raise concerns over the extent to which human life can or should be engineered. Reuters

The consortium's full version is composed of 3.055 billion base pairs, the units from which chromosomes and our genes are built, and 19,969 genes that encode proteins. Of these genes, the researchers identified about 2,000 new ones. Most of those are disabled, but 115 may still be active. The scientists also spotted about 2 million additional genetic variants, 622 of which were present in medically relevant genes.

"In the future, when someone has their genome sequenced, we will be able to identify all of the variants in their DNA and use that information to better guide their healthcare ... Truly finishing the human genome sequence was like putting on a new pair of glasses. Now that we can clearly see everything, we are one step closer to understanding what it all means," said Adam Phillippy, co-chair of the consortium that undertook the research, said.

Researchers have designed and synthesized a minimal bacterial genome, containing only the genes necessary for life. This material relates to a paper that appeared in the March 25, 2016, issue of Science, published by AAAS. The paper, by C.A. Hutchison III at J. Craig Venter Institute in La Jolla, Calif., and colleagues was titled, "Design and synthesis of a minimal bacterial genome." C. Bickel / Science (2016)

The now-complete human genome sequence will be particularly valuable for studies that aim to establish comprehensive views of human genomic variation, or how people's DNA differs, NIH said.

Many early-career researchers and trainees played pivotal roles, including researchers from Johns Hopkins University, Baltimore; University of Connecticut, Storrs; University of California, Davis; Howard Hughes Medical Institute, Chevy Chase, Maryland; and the National Institute of Standards and Technology, Gaithersburg, Maryland.