An analysis of whole-exome sequencing data found no enrichment of rare variants in genes that had been tied to Parkinson's disease by genome-wide association studies among patients with the condition. A University of Bergen-led team of researchers had hypothesized that rare variants at Parkinson's disease susceptibility loci could account for some of the disease's missing heritability and point to causal genes. Within three Parkinson's disease cohorts, the researchers examined rare variants within more than 160 genes, but while they uncovered a trend toward enrichment for three genes — GALC, SEC23IP and PARP9 — that finding did not survive multiple testing correction. "[O]ur results indicate that rare variant enrichment alone is unlikely to be helpful in identifying causal risk genes for PD in small to moderately sized cohorts," the researchers note in their PLOS One paper. "Larger studies are needed to determine if rare variant enrichment with small effect sizes are present in these genes."
Circulating tumor DNA can help guide the management of metastatic breast cancer patients, researchers from the Peter MacCallum Cancer Centre report in PLOS Medicine. They enrolled 234 patients with metastatic breast cancer into their study, which analyzed blood obtained from all patients at baseline and additional serial samples from a subset of patients. For 44 percent of patients, analysis of their ctDNA identified actionable alterations and, for 39 percent of those cases, how those patients were managed changed in light of those findings. "Our experience of implementing a prospective ctDNA testing program in mBC demonstrates the feasibility and value of this approach to direct patient management and supports the routine incorporation of ctDNA for molecular profiling in this disease," the team writes.
Aedes albopictus is already locally established in Portugal, according to a new phylogeographic analysis of the mosquitoes appearing in PLOS Neglected Tropical Diseases. Two Ae. albopictus populations were first detected in Portugal in 2017 and by analyzing the integrative cytochrome C oxidase I genes and mitogenomes of mosquitoes captured there between 2017 and 2018, researchers sought to better understand how the populations are related and how they were introduced. They found a high level of genetic diversity both within and between the two mosquito populations, suggesting multiple introduction events. Mitogenomic analysis further indicates the mosquitoes may have migrated from northern Portugal to the south. These findings, the researchers say, highlight "the challenges for vector surveillance and control programs aiming at restraining arbovirus disease burden in the future."