13 Dec 2012

Genetic Map of First Settlers

From Our Changing World, 9:34 pm on 13 December 2012

by Veronika Meduna


Michael Knapp working on samples of ancient DNA in a laboratory designed and built especially for this purpose to avoid contamination (images: M Knapp)

Wairau Bar in Marlborough is one of the most significant archaeological sites in New Zealand. More than 700 years ago, there was a settlement whose residents were among the first people to have stepped ashore in Aotearoa.

Archaeological excavations began in the late 1930s and the material collected from the site, most of which is now part of the collections at Canterbury Museum, provided the first conclusive evidence that New Zealand was originally settled from East Polynesia. Apart from artefacts, archaeologists also removed human remains from 44 graves for further investigations. The remains were reburied three years ago as the tangata whenua, Rangitane iwi, sought to have the koiwi tangata of their tupuna returned to their land.

A team of researchers at the University of Otago, including archaeologist Richard Walter, biological anthropologists Lisa Matisoo-Smith and Hallie Buckley and evolutionary biologist Michael Knapp, studied the skeletal remains and discovered a wealth of information about the diet and health of these pioneering navigators who became New Zealand’s first settlers.

With the permission of Rangitane iwi, the remains were also screened for DNA preservation in a study led by Lisa Matisoo-Smith. Of the 19 burials examined, four provided samples of ancient DNA that was preserved well enough to allow amplification and sequencing. In this interview, Michael Knapp explains how the team was able to sequence the complete mitochondrial genomes (which is inherited only through the mother's side) and found a surprising degree of genetic variation. They also found that all four people shared a unique genetic markers found in modern Maori and that one of the settlers carried a genetic mutation linked with insulin resistance, which leads to type 2 diabetes.

This latest study was published here (pdf).