Rare Ancestral Variant found in VIKING Health Study

DNA analysis of selected volunteers from the Shetland population identified a rare variant in the sequence of a gene that is known to be important in the control of heart rhythm.

Haplotype - Rare Variant
Analysis of DNA sharing around the gene variant (shown by the arrow)

It's know as 'long QT syndrome' and can cause an irregular heartbeat. The genetic variant was found in three volunteers within a large family. Careful investigation of all the genetic data from the three related individuals allowed their shared DNA sequences to be described in detail.

The shared DNA sequences were searched for in the genetic data of all participants in the VIKING Health Study - Shetland. This revealed two additional people with the same DNA sequence in the gene.

All five volunteers with this DNA carry the rare variant from a shared common ancestor, who probably lived in Shetland hundreds of years ago. GPs of these volunteers were told about the research findings, in line with agreed ethics, allowing them to advise on further testing. The additional participants must be distantly related, as they are not connectable within the family. Their identification, using modern "big data" computer technology, showcases the potential of this research resource for genomic medicine.  

The populations of Orkney and Shetland have a number of characteristics which are favourable for the identification of genes influencing clinical traits and disease potential. This project shows the value of the strong and enduring family links that exist in the Shetlandic population. They particularly assist in the association of DNA variants with the detailed medical data that was collected in the recruitment clinics, such as blood cholesterol, eye measures and heart rhythms (using ECGs).

This study was made possible by the whole genome sequencing collaboration with the Scottish Genomes Partnership (SGP) and has been published  in a scientific journal. The paper can be found below:

An actionable KCNH2 Long QT Syndrome variant detected by sequence and haplotype analysis in a population research cohort