4
SOMEWHERE in Siberia, tucked away in the Altai mountains, scientists and archaeologists have discovered evidence of what is being called the very first human family. Scientists tested the remains of 13 bodies that were found in or around the mouths of two caves. The DNA sequencing of the remains showed that a father and daughter lived there along with other relatives including possible cousins. All of this happened 50,000 years ago. Now scientists say that they have found that the DNA inherited from this type of human (Neanderthal) could be a major factor in predicting severe Covid infections.
We would not know anything about this Neanderthal family or the link between Covid-19 and the presence of Neanderthal DNA if it were not for a Swedish geneticist Svante Pääbo. Much to the surprise of other geneticists, Pääbo found a way to extract and then sequence the DNA of ancient humans. This year, this scientist was awarded the Nobel Prize for Medicine for his contribution. It can be said that without Pääbo we would have a very different picture of our past. Not only would we not know that ancient humans like the one whose remains have been found in Russia were already living in families but also miss important connections between ancient human DNA and our contemporary susceptibility to novel viruses like Covid-19.
Neanderthals may not be around any longer, but at the time that these caves were inhabited, there were several different types of humans around. The remains of Denisovans, yet another kind of human, were found in a nearby cave even though they lived several thousand years before the Neanderthals who lived there. Further exploration of the cave has yielded plenty of bison and horse bones, showing that the inhabitants were hunter-gatherers and ate a diet of mostly meat. The Neanderthals living in the two caves appeared to have socialised. The DNA also revealed that it was women who left the group in which they were born and joined another group and stayed there.
The discovery is quite fascinating because the picture of the social structures of ancient humans has been incomplete. The retrieval of two more sets of bones, that of a man and woman, suggests that there may even have been social relationships between the two groups. Proof of all this transforms what we know about Neanderthals and their capabilities. The fact that they lived in very small communities may provide some clues as to why Neanderthals became extinct and Homo sapiens became ascendant.
It is awe-inspiring to consider that other kind of humans were probably living in family units and sharing food by the fire thousands of years ago.
Then there is the link with Covid-19, which, given that Homo sapiens’ ascendancy is linked to the extinction of Neanderthals, seems a bit like an ancient genetic curse. Pääbo’s study of the Covid-19 connection, published in the journal Nature, discovered that in the region around chromosome 3 an errant haplotype from Neanderthals has been found. A map published with the study lays out which geographical regions have the largest populations of people with the Neanderthal gene. While the Neanderthal sequence can be found in the DNA of people all over the world including Western Europe, it is said to be especially high in the Indian subcontinent. Would the high incidence of Covid-19 fatalities and hospitalisations be associated with it? Naturally, it would mean that many people in Pakistan are also likely to carry the variant.
The connection between the presence of Neanderthal DNA in our genome does not explain everything about severe Covid-19, but it may provide a path to understanding how both vaccines as well as medicines will be tailored to a person’s particular DNA sequence. In the Western world, doctors have already begun to do this. The BRCA 1 and BRCA2, which predict breast cancer, for example, have led to many women choosing to have pre-emptive radical mastectomies and hysterectomies in an effort to avoid cancer. In other cases, people can find out what awaits them in later years but not necessarily be able to do anything about it. This is true for the gene that predicts whether a person will develop early onset Alzheimer’s disease. In cases like those, it would be a matter of personal choice whether or not one chooses to find out about what will happen to them in the future in connection with their health.
Fifty thousand years is a very long time to imagine. In comparison, our own civilisation, a little over 2,000 years old, does seem so small and insignificant. But, at the same time, it is awe-inspiring to consider that other kind of humans were probably living in family units and sharing food by the fire so many, many thousands of years ago. Women would be moving away from their birth families, which may explain the high genetic diversity along maternal lines. It is unknown, of course, how and where they met or how the women made it from one small Neanderthal settlement to another.
We humans share most of our genetic code with ancient Homo sapiens who are seen as the ultimate cause of the Neanderthal extinction. The fact that little has changed for humans genetically means that many of the attributes we have are the ones that were suited to life tens of thousands of years ago. We may sit typing at a computer all day long or travel in jet planes, but our bodies and perhaps even our minds were better suited to hunting and gathering rather than sitting around all day long. Our civilisation will someday be excavated by some enterprising scientist like Svante Pääbo, who comes along, digs up our bones and iPhones, and makes guesses about our social structure. Perhaps, to future archeologists, our lives will appear just as limited and brutish as the Neanderthal family that we have only recently met.
The writer is an attorney teaching constitutional law and political philosophy.
Published in Dawn, October 26th, 2022
