Immunity system complexity: Devonian immune genes (Introduction)

by David Turell , Monday, June 15, 2020, 20:40 (1410 days ago) @ David Turell

Now being found across the Pacific Archipelago:

https://medicalxpress.com/news/2020-06-immune-properties-ancient-dna-isolated.html

"Could remnants of DNA from a now extinct human subspecies known as the Denisovans help boost the immune functions of modern humans?

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"Scientists studied genomic diversity among 116 individuals from three Indonesian populations: the Mentawai on the west coast of Sumatra; the Sumba in central Indonesia; and the Korowai, a group of hunter-gatherers from the western side of the isle of New Guinea.

"The Korowai are of particular interest, as their DNA holds the world's last remaining significant remnants of genetic code—as much as 5%—from a cousin of modern humans called the Denisovans, the study says. Like the better-known Neanderthals of Europe, the Denisovans of Asia also are an extinct human subspecies who lived tens of thousands of years ago. And just as Neanderthals passed on certain immune properties to those of European ancestry, the Denisovans may have passed on protective immune genes to their southeast Asian decedents.

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"Dr. Nicholas Banovich, an Assistant Professor in TGen's Integrated Cancer Genomics Division, a human geneticist, and a senior author of this PLOS Genetics paper, said the study's results highlight genes involved in the function of immune cells. This suggests a potentially adaptive response to local environmental pressures, including pressures from various tropical diseases.

"'One of the unique aspects of Indonesia is individuals on the island of New Guinea have high remnants of DNA from one of our extinct ancestors, the Denisovans," Dr. Banovich said. "We found these remnants of ancient DNA are driving changes in genes involved in immune function. This study demonstrates the power of including understudied populations in an effort to increase the overall understanding of human genetics."

"The international team is continuing its study, integrating more genetic data, exploring patterns of local ancestry and how archaic human genes are imbedded in modern-day populations.

"'We are now attempting to pinpoint individual genetic changes—in particular, those that are carried over in these remnant DNA fragments from Denisovans—which regulate how much or how little a gene is turned on, and how these genetic changes may shape immune response," Dr. Natri said."

Comment: Same story. Different homo species developed different forms of immunity based on geographical location. The immune programs which respond as necessary are all the same in each species.