Genetic Links Found to Chronic Lymphocytic Leukemia

Genome-wide association studies (GWAS) of chronic lymphocytic leukemia (CLL) have shown that common genetic variation contributes to the heritable risk of CLL.

Four new regions of the genome linked with an increase in susceptibility to CLL have been identified, which suggest that this common type of blood cancer may develop partly as a result of faults in telomeres.

Scientists at The Institute of Cancer Research (Sutton, Surrey, UK) and their international collaborators analyzed the genomes of 1,739 patients with CLL and 5,199 healthy adults. The study linked four single nucleotide polymorphisms (SNPs) with susceptibility to CLL. They conducted an independent primary scan of CLL and performed a genome-wide meta-analysis with a previously published GWAS followed by analysis of the top SNPs in two separate case-control series.

In the primary scan they genotyped 1,271 cases using the Omni Express BeadChip (Illumina, San Diego, CA, USA). The total number of risk variants for CLL identified is now 30, with the genetic factors newly identified by the study found around a set of genes responsible for the function of telomeres.

CLL is the most common form of leukemia in western countries, with over 3,000 people diagnosed in the UK each year. It is a slowly progressing and currently incurable form of cancer that affects blood-producing cells in the bone marrow. Close relatives of CLL patients are at eight times higher risk of being diagnosed than the general population.

Richard Houlston, MD, PhD, a professor of Molecular and Population Genetics at The Institute of Cancer Research, said: “We are starting to complete the picture of how CLL development is dictated by mutations in regions of the genome connected to specific aspects of DNA repair. These genetic factors explain a significant proportion of inherited cases of CLL.” The study was published on December 1, 2013, in the journal Nature Genetics.

Related Links:
The Institute of Cancer Research
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