Abstract Science: July 13-17
Progress with Parkinson's, robust genetic markers for depression and why it's so hard to develop a global AIDS vaccine. This week in Abstract Science.
(GEN, 7/14/2015, Patricia Fitzpatrick Dimond)
Significant progress in defining the molecular causes of Parkinson’s disease is providing novel drug targets, which researchers hope will point us toward better treatments for this progressive movement disorder. In the 15 years since US scientists identified defects in a gene linked to PD in some families, 13 loci and nine genes have been identified using a variety of sequencing methods. These discoveries are now providing the rationale, molecular insight and research tools to develop neuroprotective and disease-modifying therapies. Many of these therapies are trying to prevent the neurotoxic aggregation of α-synuclein into Lewy bodies, the protein clumps that are the pathological hallmark of PD.
(Nature, 7/15/2015, Heidi Ledford)
Depression, which afflicts some 350 million people, is responsible for more "years lost" to disability than any other condition worldwide. Identifying robust genetic biomarkers—those that apply to large swathes of the patient population—could be uniquely valuable in the hunt for better drugs and diagnostic tools. Yet efforts to find these links have been unsuccessful until scientists, quite surprisingly, unearthed two genetic sequences that seem to be linked to depression: one in a stretch of DNA that codes for an enzyme whose function is not fully understood, and the other next to the gene SIRT1, which is important for energy-producing cell structures called mitochondria. The correlations were confirmed in another set of more than 3,000 depressed men and women and over 3,000 controls. The findings are all the more astounding considering the fact that earlier studies conducted in other large cohorts of patients turned up empty. The study, led by University of Oxford geneticist Jonathan Flint, appeared this week in Nature.
(The Scientist, 7/15/2015, Anna Azvolinsky)
Most public health scientists agree that a safe and effective vaccine is needed to end the AIDS pandemic. Getting there has been a Sisyphean effort, though. The only example of vaccine-induced protection—a prime-boost regimen tested in the 16,000 person Thai trail known as RV144—was only 33% effective and it is still not entirely clear why some volunteers were protected and others were not. A recent study appearing this week in Science Translational Medicine that analyzed samples from this study conducted during the last decade identified a subgroup of study participants who express a human leukocyte antigen (HLA) allele linked to reduced risk of HIV infection after vaccination. Whether or not the findings from this analysis are enough to advance the development of an AIDS vaccine capable of providing global protection is an open question, however. Some scientists are doubtful, others more hopeful.
—Compiled by Senior Scientific Writer Regina McEnery and David Clark, Director of Computer-aided Drug Design (CADD) and Information Services at Argenta (now part of Charles River Early Discovery)