Huge Genetic Diversity among Papuan New Guinean Peoples Revealed

With approximately 850 domestic languages, which account for over 10 per cent of the world’s total, Papua New Guinea is the most linguistically diverse country in the world. To discover if the linguistic and cultural diversity was echoed in the genetic structure of the population, researchers studied the genomes of 381 Papuan New Guinean people from 85 different language groups within the country.

The researchers looked at more than a million genetic positions in the genome of each individual, and compared them to investigate genetic similarities and differences. They found that groups of people speaking different languages were surprisingly genetically distinct from each other.

Credit: Wellcome Trust Sanger Institute

“This is the first large-scale study of genetic diversity and population history in Papua New Guinea. Our study revealed that the genetic differences between groups of people there are generally very strong, often much stronger even than between major populations within all of Europe or all of East Asia.” says Anders Bergström, the first author on the paper from the Wellcome Trust Sanger Institute

“We found a striking difference between the groups of people who live in the mountainous highlands and those in the lowlands, with genetic separation dating back 10,000-20,000 years between the two. This makes sense culturally, as the highland groups historically have kept to themselves, but such a strong genetic barrier between otherwise geographically close groups is still very unusual and fascinating.” says Professor Stephen J. Oppenheimer, second author of the paper from the Wellcome Trust Centre for Human Genetics, University of Oxford*

Credit: CIA Fact Book

Human evolution in Europe and Asia has been greatly influenced by the development of agriculture around 10,000 years ago. When small bands of hunter-gatherers settled into villages and started farming, they expanded and over time gave rise to more genetically homogenous (similar) societies. However, despite the independent development of agriculture in Papua New Guinea at about the same time, the same process of homogenization did not occur here. This may indicate that other historical processes in Europe and Asia, such as the later Bronze and Iron Ages, were the key events that shaped the current genetic structure of those populations.

“Using genetics, we were able to see that people on the island of New Guinea evolved independently from rest of the world for much of the last 50,000 years. This study allows us to glimpse a different version of human evolution from that in Europe and Asia, one in which there was agriculture but no later Bronze Age or Iron Age. Papua New Guinea might show the genetic, cultural and linguistic diversity that many settled human societies would have had before these technological transformations.” says Dr Chris Tyler-Smith, corresponding author on the paper from the Wellcome Trust Sanger Institute 

Contacts and sources:

Dr Samantha Wynne
Wellcome Trust Sanger Institute

Citation: Anders Bergström et al. (2017) A Neolithic expansion, but strong genetic structure, in the independent history of New Guinea. Science. DOI: 10.1126/science.aan3842.