Meet !Gubi, the tribal elder of a group of Bushmen (or Khoisan), one of the oldest known human lineages. He lives the life of a hunter-gatherer in the Namibian part of the Kalahari Desert. But he also has a strange connection to James Watson, the British American scientist who helped to discover the structure of DNA. For a start, they’re both around 80 years old. But more importantly, they are two of just 11 humans to have their entire genomes sequenced.
Along with Archbishop Desmond Tutu, !Gubi is one of two southern Africans, whose full genomes have been sequenced by Stephan Schuster and an international team of scientists . Schuster’s team also analysed the genes of three other Bushmen – G/aq’o, D#kgao and !Aıˆ (see footnote for pronunciation guide) – focusing on the parts of their genome that codes for proteins. Like, !Gubi, these men are tribal elders and all are around 80 years old. Despite the fact that the four Bushmen come from neighbouring parts of the Kalahari, their genetic diversity is astounding. Pick any two and peer into their genomes and you’d see more variety than you would between a European and an Asian.
This diversity reveals just how important it is to include African people in genome sequencing projects. Until now, the nine complete human genomes have included just one African – a Yoruban man from Nigeria. The rest have hailed from Europe, America, China, Korea and, most recently, Greenland circa 4,000 years ago. This is a major oversight. Africa is the birthplace of humanity and its people are the most genetically diverse on the planet. To understand human genetics without understanding Africa is like trying to learn a language by only looking at words starting with z.
The Bushmen certainly provide a glimpse into this diversity. Desmond Tutu was also selected because his ancestry covers the two largest of southern Africa’s Bantu groups – the Tswama and the Nguni – making him an excellent representative for many southern Africans. Vanessa Hayes, who worked on the study, says, “This work is very expensive so we wanted to maximise the amount of diversity we could get in one individual.” The team had other reasons for sequencing the bishop.”He’s a voice for southern Africans and for his people. He’s a chairman of the Global Elders. He provides a genome with a lot of medical history behind it, having survived prostate cancer, polio and Tb, diseases that affect many southern Africans.” But most importantly, Hayes says, “He wanted to participate. He himself wanted to study medicine so this for him was a personal endeavour.”
The researchers hope that their new data will allow medical research to become more inclusive. Vanessa Hayes, who led the study, says that she found HIV research in South Africa to be very difficult because most genetic databases are severely Eurocentric, which rules out a lot of Africans from medical research. Without this knowledge, for example, we have no way of knowing if a drug that was developed and tested in Western patients will have the same benefits and risks in African ones.