In PLOS Genetics, an international team led by investigators in the UK describes a mitochondrial mutation involved in a progressive kidney disease called tubulointerstitial kidney disease, which can eventually lead to renal failure. In a UK family with a maternally inherited form of the disease, the researchers did mitochondrial genome sequencing on urinary epithelial cells in affected individuals. In the process, they narrowed in on a suspicious promoter substitution that was associated with tubulointerstitial kidney disease, but didn't produce symptoms associated with typical mitochondrial disease.
Researchers from Amgen, Decode Genetics/Amgen, the University of Iceland, and elsewhere describe a rare mutation that appears to protect against asthma risk in another PLOS Genetics paper. Using genome sequences and imputed data from the Icelandic population, the team tracked down a rare, loss-of-function variant in IL33, an immune cytokine-coding gene previously implicated in asthma. The alteration, found at low allele frequencies in Icelandic and other European populations, appears to coincide with diminished IL33 transcript expression — producing a truncated transcript with diminished immune activation and asthma risk.
A team from India and the US explores gene activity patterns in Mycobacterium tuberculosis pathogens found in sputum samples from pulmonary tuberculosis cases. As they report in PLOS One, the researchers did array-based transcriptional profiling on M. tuberculosis representatives found in smear-positive tuberculosis cases. Their results suggest that mycobacterium in sputum are at a low energy infection stage marked by muted expression of genes in aerobic respiration, translation, and other pathways, though the expression of some genes with unknown function jumped in the sputum.