Revealing the hidden stories preserved in our genes

What can research at the UCL Genetics Institute tell us about ourselves? Here, Dan Jacobson reveals. 

According to oral history, the Kuba Kingdom, a flourishing dominion based in the South East region of what is now the Democratic Republic of Congo, was created by the foreign trader Shyaam a-Mbul a Ngoong. Formed in around 1625, Shyaam sought to conglomerate around 19 individual, independent chiefdoms, consisting of various ethnic groups, under his centralised control. Over time, based on Shyaam’s research of the surrounding empires, the Kuba Kingdom expanded rapidly and grew into an advanced state, with a well-needed, established culture and set of customs. This included a governmental system based on merit and democracy, a legal system including the concept of trial by jury, and even a capital city.

The kingdom thrived until the late 19th century, when Belgian colonisers arrived in the region during the era of exploration. At the time, the Kuba Kingdom had developed so far beyond the surrounding groups that the Europeans naturally assumed that Western contact had already been established prior to their arrival. Due to its isolation, it was less affected by factors such as the slave trade, which decimated the more coastal kingdoms. However, that didn’t prevent the subsequent plundering and pillaging.The Kuba Kingdom still exists today, but its numbers are significantly reduced.

The Kuba Kingdom has been of considerable interest to historians and anthropologists, who have associated its innovative structure with both the greatest ancient kingdoms and modern-day states. Unfortunately, little written documentation exists, suggesting that an alternative method is required to allow us to learn more about this comparatively mysterious time. Novel techniques in genetics and genomics are now being utilised in an attempt to reclaim this lost story.

As part of recent research based at the UCL Genetics Institute, geneticists and historians have come together in order to identify the genetic changes which could have arisen as a result of the state centralisation catalysed by Shyaam, known as a ‘genetic legacy’. Using data obtained from current Kuba people, as well as surrounding individuals who did not descend from the Kuba Kingdom, researchers found that descendants displayed significantly higher genetic diversity than individuals from surrounding groups, implying a greater level of intermixing and integration in line with the oral history described. In this way, it has been demonstrated that genetics preserves the stories which many sought to destroy and suggests that we, in fact, could be an essential historical source in the continued investigation of our collective history.

The idea of using genetics to discern information concerning our ancestry has become increasingly prevalent. Biotechnology companies such as 23andMe now offer DNA testing specifically for the purpose of determining your ancestry. Customers provide a saliva sample that undergoes single nucleotide polymorphism (SNP) genotyping, a technique used to measure the variation across a population of SNPs. These are single base changes at specific positions in the genome that account for a significant proportion of variation in characteristics observed throughout the species. The genome of the customer is then compared to complete genomes of individuals from regions throughout the world, and a computational algorithm is used to match specific regions of the customer’s DNA to given reference genomes. If your results describe you as 11% Iberian, for example, this means that 11% of your genome was most closely matched to what is known of the genome of the Iberian population living today (according to the company conducting the analyses). It is these tests which were used to determine the genetic diversities of the Kuba people and their neighbours.

In reality, these tests don’t determine your ancestry per se, but use comparisons to living individuals as a proxy for where your ancestors may have dwelled. Additionally, companies such as this have had to struggle with a variety of ethical concerns. 23andMe initially provided DNA tests in order to identify mutations in the genome which may alter the customer’s risk of developing certain diseases, a service which is now being offered to healthy patients by the NHS. However, a customer intended to learn more about their ancestry may not want to be made aware of this kind of information.

Questions have also arisen regarding the ability for 23andMe to obtain informed consent, as the company is able to capture additional information via the online browsing habits of its customers.And the holiday season, a particularly busy year for the company, offered many tabloid snippets, from the realisation of adoption following testing to UKIP supporters finding out that they have European ancestry. However, the motivation for individuals to submit these tests is driven by the empowerment they acquire by having better knowledge of who they are and where they come from. With a more effective, universal technique of describing an individual’s history, surely this can be extended to that of a population?

Recently, this concept has been embraced in order to investigate the history of Native Australians. The Aboriginal Heritage Project, a group of researchers based at the University of Adelaide, have been analysing DNA from an extensive collection of hair samples to piece together the dynamics of the native human population following initial migration to the island approximately 50,000 years ago. They have found that the first Aborigines colonised the entirety of the coastal region of Australia very rapidly following their arrival, creating a pattern which was effectively maintained until the colonisation of Australia in 1788. Professor Alan Cooper, Director of the Australian Centre for Ancient DNA, said that he hoped the project would lead to a “rewriting of the history textbooks”, and hopes that it could provide a grounding for the wider population to understand the bond between Australia and the Aboriginal population.

Undeniably, one important, and in my opinion noble, reason for seeking to add to the current historical record centres around the concept of ‘knowledge for knowledge’s sake’. It is human nature to consolidate what we currently know and investigate what we don’t. However, the key motivation behind research of this kind stems from the realisation that the human story is not told equally, wherein the histories of some groups are presented as richer.

As a biology student, it is interesting and refreshing to consider a scientific concept for which the overarching goal is not as tangible as increasing crop production or finding a cure for cancer. Indeed, population genetics, and understanding the past migrations of our species, do offer potential for future work. It could help us understand how populations in Ethiopia, Tibet and the Andes have independently evolved to enable life at high altitude, or why populations in countries such as Finland are more prone to genetic disorders. However, whilst it is understood that everyone’s story is worth telling, we now have the tools to allow this to happen. In a video for the genealogy company Ancestry.com, one volunteer argued that tests like this should be compulsory, claiming that “there would be no such thing as extremism in the world if people knew their heritage.” A statement as bold as this may be naïve, but the power of a shared ancestry may be underestimated and could offer the opportunity for an entirely new demographic to be proud of their roots.