Population Based Genetic Research

One of the greatest obstacles to the development of effective therapies for motor neurone disease (MND) is our incomplete understanding of its underlying causes. For amyotrophic lateral sclerosis (ALS), the most common form of MND, it has been established that genetic risk factors play an important role in an individual’s risk to develop the disease. This means that an individual with ALS has inherited something from their parents that causes ALS either directly or by acting in combination with other risks such as environmental or occupational exposures. Understanding exactly what all of these risks are and how they act to cause neurodegeneration will vastly improve our capacity to seek out new therapies in an informed and targeted manner.

Genetic information is encoded in DNA – the language of life and evolution that uses just four letters in various combinations to spell out exactly how to make and maintain an organism such as a human. The entirety of one individual’s DNA is called their genome, and everyone’s genome is unique. The uniqueness of someone’s genome is what determines the uniqueness of their characteristics, including whether or not they have a disease. Just as a book can have a typographic error that changes the meaning of a sentence, a genome can have a similar mistake, called a mutation, that changes the way certain cells grow or function. The goal of the genetics arm of the Irish ALS research group is to find the mutations that lead motor neurones to die in ALS so that we can develop interventions that correct these mistakes.

Because genomes contain many differences that have nothing to do with disease but instead determine benign characteristics such as eye colour, height, etc, we need to examine DNA from a very large number of people to find the mutations that cause ALS. For this reason, we are a part of Project MinE, a major DNA sequencing initiative that is examining the complete genomes of 15,000 ALS patients along with 7,500 healthy individuals with no disease, for comparison. Through crowdfunding and support from SFI, the Irish group is contributing 1,050 individuals to this project alongside several other participating countries. By analysing the vast amount of data that is returned from this project, we will identify the mutations that cause ALS which will lead us one step closer to a cure.

This work is also generating a large volume of data that allow researchers to explore the genetic landscape of the Irish population, which is itself an important component of ALS genetics research as it helps us to distinguish confounding bias from real signals of disease risk. Our work is being carried out in collaboration with Dr Russell McLaughlin (Complex Trait Genomics, Trinity College), Professor Dan Bradley (Population Genetics, Trinity College) and the many research groups involved in the Project MinE Consortium (led by Professors Leonard van den Berg and Jan Veldink at UMC Utrecht).