A systems biology-based analysis of postmortem brain samples from individuals with late-onset Alzheimer's disease suggests a microglial cell and immune function-related network may contribute to the disease. In Cell, researchers from the US, Iceland, and elsewhere looked at gene expression patterns in 1,647 postmortem brain samples from 549 genotyped individuals, including 376 individuals with late-onset Alzheimer's disease and 173 dementia-free control individuals. A subsequent network analysis drew the team's attention to a module with ties to immune function and the action of brain cells called microglia as well as a gene that appears to help regulate this network.
GenomeWeb Daily News has more on the study, here.
Researchers from the US, Italy, and Israel present a punctuated evolution mutation model for prostate cancer in another Cell paper. That team performed genome sequencing on matched tumor and normal samples from nearly 60 men with prostate cancer, using the data to model — and retrace the history — of genomic rearrangements in the tumors. The patterns they saw hinted that inter-dependent translocations and deletions can arise through a rush of rearrangement that study authors dubbed 'chromoplexy.' "Our modeling suggests that chromoplexy may induce considerable genomic derangement over relatively few events in prostate cancer and other neoplasms," study authors write, "supporting a model of punctuated cancer evolution."
Check out GWDN for more on the study, too.
Finally, Harvard Medical School and Children's Hospital Boston researcher Peter Park and his collaborators from the US, China, and Korea report on a catalog of somatic structural variations in cancer genomes from 10 cancer types. The group came up with the collection using genome sequence data for tumor-normal samples from 140 individuals with cancer, and an algorithm that unearths structural variants from short read sequence data. With this information, the researchers then delved into the mechanisms behind the alterations, such as double-stranded DNA breaks and errors arising during DNA replication.