DUBAI, United Arab Emirates (CNN) — Scientists have compiled a new draft of the human genome that better captures the genetic diversity of the human race.

The new pangenome includes DNA from 47 individuals from every continent except Antarctica and Oceania. This could improve our ability to diagnose disease, discover new drugs and understand genetic variations that lead to poor health or a particular physical trait, said participating scientists.

Until now, geneticists have used a single human genome, often based on an individual, as a standard reference map for identifying disease-causing genetic mutations. This may have missed some of the genetic variation between individuals and different populations around the world.

“This reference pangenome represents a significant scientific achievement, providing an expanded view of humanity’s DNA map, with greater human diversity than previous reference sequences,” Eric Green, director of the US National Institute of Human Genome Research, which funded the project, said at a press conference.

“Having a high-quality human genome assembly that increasingly reflects human diversity helps scientists and healthcare professionals better understand how genetic variations affect health and disease, and moves us toward a future where genetic medicine benefits everyone,” said Green.

Pangenome, a digital fusion of sequences that can be used to compare, construct, and analyze other human genome sequences, is still in draft form. Researchers hope to have 350 on board by mid-2024. The scientific achievement was described in several articles published Wednesday in Nature and its partner journals.

Assistant Professor Benjamin Schwessinger of the Australian National University, who was not involved in the project, explained that you could imagine the feat as a new blueprint for getting your kids to school. Instead of taking the same route every day, your neighbor on the next street might take a slightly different route.”

This new, pan-genome approach “maps these alternative pathways that make us human,” Schweisinger said in a statement.

Genetic variation

While each person’s genome varies slightly, about 0.4% on average from the next, the human genome is huge, containing 3.2 billion pairs. This means that there are still many important genetic differences between individuals and populations around the world.

The four building blocks of DNA – adenine (A), cytosine (C), guanine (G) and thymine (T) – form specific pairs, and the interaction of these base pairs creates the structure of DNA.

Genetic variation can be small, differences in one or a few DNA bases, or large structural variations of 50 base pairs or more. These large structural variables may have important health implications, such as immune system function.

The new reference covers the most diverse gene sequences and adds 119 million base pairs to the library of 3.2 billion base pairs previously known to make up the human genome, further enriching our understanding of human genetic diversity.

“The pangenome reveals the structure of diversity and how it affects genes and will have a huge impact on genetic research,” said Benedict Button, associate professor of biomolecular engineering at the University of California, Santa Cruz and co-director of the University of California, Santa Cruz. , Santa Cruz Genomics Institute.

“It also reveals new biology,” he said. “We’re getting a better picture of how some complex regions of the genome diverge. Until now, the composition of these rapidly evolving regions has been largely invisible to us.”

The first draft of the human genome was published in 2001 and was not fully completed until 2022. “It’s a great tool,” said Karen Mega, an associate professor in the Department of Biomechanics at the University of California, Santa Cruz. and Associate Director of the Genomics Institute at UC Santa Cruz. He was invaluable to researchers and ushered in a new era of scientific discovery, technological innovation and genetic medicine.”

“Understanding and cataloging these differences between genes will help us understand how cells work and their biology, understanding genetic differences and how they contribute to understanding human diseases,” Megha added.

Eliminate bias

According to NHGRI, the original human reference genome was based on anonymous volunteers who responded to an advertisement in the Buffalo Evening News on March 23, 1997.

47 anonymous individuals were included among the participants in the 1000 Genomes project, a shared catalog of human genetic diversity completed in 2015. People who are not included in the 1000 Genomes Project are particularly those of Middle Eastern and African descent.

Other projects aimed at expanding genetic databases “often miss the mark in showing respect for communities and indigenous peoples” in low-income countries, who say their samples and data are used to further the goals of scientists and institutions in rich countries. Published in Nature this year.

The team made sure to avoid such mistakes. Barbara Koenig, professor of medical anthropology and bioethics at the University of California, San Francisco, said ethical considerations and a “principle of justice” are a key part of our effort.