Genetic Mosaicism Factored into Cancer Development
(ChemotherapyAdvisor) – Genetic mosaicism is linked to development of cancer, according to a team of researchers of several U.S.–based research institutions. This conclusion is based on a paper entitled “Detectable Clonal Mosaicism from Birth to Old Age and its Relationship to Cancer,” which was published online in Nature Genetics on May 6.
The investigators aimed to identify the relationship between lifetime genetic mosaicism and the development of cancer. Single nucleotide polymorphism (SNP) microarray data from over 50,000 individuals were recruited to perform genome-wide association studies. From these studies, the investigators detected clonal mosaicism for large chromosomal abnormalities, including duplications, deletions, and uniparental disomy. According to the investigators, the SNP-based detection method “requires a relatively high frequency of cells with the same abnormal karyotype (>5–10%; presumably of clonal origin) in the presence of normal cells.”
The investigators reported a low frequency of detectable clonal mosaicism in peripheral blood (<0.5%) from birth until 50 years of age. They observed that, after age 50, the frequency of detectable clonal mosaicism, rapidly rises to 2–3%. “Many of the mosaic anomalies are characteristic of those found in hematological cancers and identify common deleted regions with genes previously associated with these cancers,” the investigators wrote. “Although only 3% of subjects with detectable clonal mosaicism had any record of hematological cancer before DNA sampling, those without a previous diagnosis have an estimated 10-fold higher risk of a subsequent hematological cancer (95% confidence interval: 6–18).”