Two new gene variants, which each increase the risk of bone marrow cancer by 30 percent, have been identified by scientists at the Institute for Cancer Research.
The cancer, known as multiple myeloma, affects the white blood cells of the bone marrow and around 4,000 people in the UK develop it each year. Relatives of patients have four times the chance of developing the disease.
So far it has been hard to pinpoint which genes may be involved, although it is also likely that the increased risk is partially due to environmental factors.
'This study is the first to confirm that some people are genetically predisposed to multiple myeloma', says lead author Professor Richard Houlston.
The team used genome-wide association studies (GWAS) to compare the DNA of 1,675 patients to that of 5,900 people without the cancer. They identified two SNPs — single letter variations in the DNA code — that were more frequent in the multiple myeloma patients' genetic codes.
'Compared to other cancer types, relatively little is known about the biological processes that cause this form of the disease. By identifying these genetic variants, we are closer to understanding how this cancer develops', continues Professor Houlston.
The first variation, increasing risk of myeloma by 32 percent was in a gene called ULK4, located near to a gene on chromosome 3 that produces TRAK1 protein, which is responsible for moving proteins and organelles around the cell. The second variant, found in DNAH11 on chromosome 7, increased the risk by 38 percent and was located close to a gene involved in cell division, CDCA7L.
However, these changes were not found to affect the proteins these genes produce, and so the exact contribution of these variants to the disease remains unclear. As these genetic changes account for around four percent of the total risk other variants are also likely to be involved.
Professor Gareth Morgan, another senior author, says: 'By learning more about the biology of multiple myeloma development, we hope to identify new drug targets — or even existing drugs — that could improve patient outcomes. Multiple myeloma is becoming more common as the population ages, and so it is even more important that we find new treatments'.