A large team led by researchers in the Netherlands and London conducted the largest-ever MND genetic analysis, which brought together the efforts of over 180 scientists from 17 different countries. Using DNA samples donated by over 12,000 patients with MND and over 23,000 by healthy individuals, millions of common genetic variations were profiled in all subjects. These were compared between MND patients and healthy individuals to help to understand what genetic variation may cause the disease.

There are around 110 new cases of MND each year in Ireland, with those affected typically between 50 and 70 years old. Individuals diagnosed with MND suffer progressive paralysis, which ultimately leads to death, typically within 3-5 years of the first symptoms. Both genetic and environmental factors are known to play a role in the development of MND, but pinpointing and understanding the genetic causes will help to hasten the development of effective treatments for what is currently an incurable disease.

The new study, published in leading journal Nature Genetics, pointed the scientists towards three previously-unknown genes, and also provided the best indication yet of how exactly scientists should continue their search for the causes of MND.

Dr Russell McLaughlin of Trinity is one of the lead authors of the study. He said: "Some diseases, like schizophrenia, appear to be caused by the added effects of thousands of genes commonly seen in the population, each of which could not cause the disease on its own. With MND, it seems that a similar mechanism may be at play, but the genes that add up to cause the disease are much more rare."

This apparent rarity of genes that cause MND means that scientists are now tasked with conducting even larger and more fine-grained studies to uncover the remainder of what causes the disease. Research is already under way in Trinity and several other countries that will expand the search beyond common genetic variation to include genes only seen in a small number of people.

Project MinE (www.projectmine.com/country/ireland) is a crowd-funded initiative that will examine the full DNA profile, including rare genetic variation, in 1,000 Irish individuals to determine all of the genetic causes of MND. But genetic research is costly, and Professor Orla Hardiman, who leads the Irish MND Research Group, hopes that the public will help to fund the initiative.

Professor Hardiman said: "With Project MinE, everyone has the opportunity to get involved in helping to discover the many causes of MND, in the hope that one day we will have a cure for this devastating disease."

The information obtained in Project MinE will be shared freely with all collaborators in the initiative and made available to scientists researching drug development.