Genomics service companies and their reach to people are getting more and more evident. Sending a sample of your saliva gets you the information about your genetically similar cousins from a geographically different location, which you probably have not even visited in your entire life. Where did all this begin and what is the business of knowing your ancestry through your genes all about? If you are curious, read ahead.
The so-called famous Human Genome Project (HGP), which emerged as a grand celebration in the field of genetics, is the backbone of knowing your ancestry. Testing for ancestral genetics is made possible because of SNPs (abbreviated from ‘single nucleotide polymorphisms’ and pronounced as ‘snips’). I have previously explained them in my blog ‘Unify in the name of genetics‘. They are the polymorphic sites that define our differences, yet makes us all functionally alike.
The permutations and combinations of these SNPs among the human population are obviously varied and thus, we are defined by our ethnicity and/or geographic location. But are we all so different really? This is where human evolution utilizes the power of SNP knowledge. Combinations of SNP sequences changes each time there is a sexual reproduction and a new human is born. These combinations are called haplotypes.
Through the Human Genome Project, a plethora of haplotype sequences combinations can be obtained. With the help of computers and mathematics, we can now compare and trace back their origin, which means ancestral genomics. We can trace back the origin of one human, based on percentage of similarity they carry of the common haplotypes, that are identified to be unique in a particular geographically human population (A hard-hitting truth for all the religious freaks, racists, and other types of discriminators, who are trying hard to protect their culture, their ancestry, their roots). We were the same at one point of time, we got distributed just like all the other creatures on earth – birds, mammals, insects, etc. because of change in nature and our natural need for survival. We survived the changing climate and many of our ancestors had no caste or religion or God they particularly worshipped. Our creation made us survive better in a particular environment and we continued to grow with those genetic changes. We will continue to do so. There is no you and me. There is just us! Tomorrow if Earth is undergoing a catastrophe, the fittest organisms are going to survive because of their genetic makeup. We are all interconnected and the more connected we stay, the stronger we will survive the changing nature.
So what is the use of knowing your ancestral genome makeup? I truly can’t explain a benefit to anybody’s current life. It’s a luxury, a fun-fact or an adventure of knowing yourself. However, it does carry a baggage of unknowns which you might believe without having absolute surety. That can be taxing to your emotional well-being. Definitely, for researchers, it is going to be useful information to combine this information and map back the history of human population geographic split.
The same SNP information is used to compare the collective human genome data for identifying disease risk variants. Again there is no surety of such diseases to occur. It’s all in the name of probability. Increased probability of having a disease means that the data collected, so far, on those particular variants shown to support the occurrence of disease, is high. You will never know how many humans have the actual disease according to that data. It definitely doesn’t include the genome of the whole world population. More information about this can be read in my previous blog – ‘Limit your genetic worries‘.
Why are we having these companies in place and allowing them to test? We have millions of products in this world which get approved. As consumers, we need to be aware of what we choose. The real downside of direct-to-consumer tests is the breach of privacy. Companies can misuse the genetic information to their benefit and an average informed person won’t know it at all. Recently, a company has offered to the US government to help the separated families reunite by obtaining their blood and conducting genetic testing on them. It sounds so benevolent. But no! They might be willing to do it for free, however, just by obtaining that information, companies can conduct so much research and monopolize the genomic service market. Choose your genomic product services wisely!
If you still want to go for ancestral genetics, go for mitochondrial or Y-chromosome genomics. Mitochondria are a part of all our cells which we get from our mother because we get nurtured from her egg cell which has her mitochondria and that’s what gets passed on to us and every cell of our body. Every mitochondrion has it’s own DNA material, whose functions are still being explored. However, it’s a fact to understand that it is conserved and inherited in all of us from our great-great-great grandmothers. Similarly, chromosome Y which differentiates males from females is only inherited paternally. You can rest assured you carry the same Y chromosome as your great-great-great grandfather (Although they do recombine with the mother’s X chromosome and change a little over course of generation). These DNA sequences can really help trace your ancestry. But guess what, we don’t have data of your great-great-great grandfather or grandmother, so good luck with trusting the companies for that information.
A really good technical overview on this topic – https://youtu.be/FrpJ7HFKY8o. I hope this was interesting to curious minds!