High levels of rare genetic variation found in Shetland

A recent study, using data from VIKING Health Study-Shetland volunteers, has found high levels of rare genetic variation.

Shetland Isolated Buildings

Our volunteers have provided a valuable window into understanding the roles of rare genetic variants in human traits and diseases. The Shetland Isles have an unusual history that is distinct from the rest of the British Isles. They have strong family relationships that still exist today. This has led to high numbers of some genetic variants that are very rare elsewhere. 

The University of Edinburgh research team is based at the Medical Research Council Human Genetics Unit. They made this finding by studying the whole genome sequences of 500 VIKING Health Study-Shetland volunteers. Whole genome sequencing is used to read all of someone’s DNA code. They compared what they found to a sample of people from mainland Scotland, living in or near Edinburgh. 

It was remarkable that one tenth of all the genetic variants found were at least 10 times more common in Shetland than in Lothian.  All in all, many thousands of ultra-rare genetic variants were discovered, which had not previously been seen in other populations. 

Surprisingly, these variants are found at higher numbers in important parts of the human genome. These include gene sequences which provide the code for making proteins and sequences that regulate genes. 

Areas of the genome which control gene expression have particularly high levels of ultra-rare variants. Genetic research worldwide has shown that variants in these areas play a vital role in a person’s susceptibility to disease. 

These new results will help to drive further research on how genetic changes, found in Shetland and elsewhere, may affect the chances of illness or good health.

This paper has been published in the journal PloS Genetics. To view this paper, click the link below:

Increased ultra-rare variant load in an isolated Scottish population impacts exonic and regulatory regions