Issue 9  February 5th 2016

Schizophrenia’s strongest known genetic risk deconstructed

Quote: “This study marks a crucial turning point in the fight against mental illness… Thanks to this genetic breakthrough, we can finally see the potential for clinical tests, early detection, new treatments and even prevention.” states Bruce Cuthbert, acting director of the National Institute of Mental Health.

Schizophrenia is one of the most common serious mental health conditions in the world. The cause of this disorder has been evasive due to scientist’s inability to replicate it in living cells or animals. For the first time, researchers have identified the specific gene variant which over activates the synaptic pruning process and increases the likelihood of developing schizophrenia. Using genetic analysis of almost 100,000 DNA samples from 30 countries, postpartum brain samples from almost 700 patients, and animal models, it was identified that the complement component 4 (C4) with higher expression also had higher amounts of pruning. In the brain, “C4 binds to neurons at the points where they connect with other neurons, and signals that these connections, or synapses, should also be engulfed by immune cells,” as discussed by Clare Wilson. Schizophrenics tended to have fewer connections between neurons providing further evidence of C4’s innate connection.

Published Article: Schizophrenia risk from complex variation of complement component 4

Related Article: Rethinking schizophrenia: Taming demons without drugs

Subscribe to sequencing technology study supports use of sequencing in clinical cytogenetics, pathogenic CNV detection

Published in Genetics in Medicine, researchers from BGI-Shenzhen, The Chinese University of Hong Kong, Nanjing Medical University, and other colleagues, concluded that low-coverage whole-genome sequencing may be a feasible alternative to chromosomal microarray analyses when searching for clinically relevant copy number variations. Using low-pass genome sequencing on samples from hundreds of prenatal and postnatal samples referred for chromosomal analyses, producing informative profiles for more than 96 percent of the samples. The team's search led to 119 chromosomal abnormalities, along with 103 copy number gains or losses. The diagnostic yield differed depending on the source of the samples, peaking at more than 53 percent in the 198 miscarried fetuses considered and dropping to as low as 14.7 percent across the stillborn samples. Based on these and other findings, the study's authors contended that the work "highlights the potential for using [next-generation sequencing] to facilitate genetic diagnoses in the prenatal and postnatal samples that have not been detected by conventional karyotyping and/or [chromosomal microarray] analysis."

Good Start Genetics’ Cost Effectiveness Study Demonstrates Clinical Outcomes and Healthcare Cost Advantages

The Good Start Genetics company announced their publication in Molecular Genetics & Genomic Medicine suggesting that carrier screening utilizing the company’s next-generation sequencing (NGS) leads to better health outcomes in addition to being a cost-effective screening strategy. It was found that decreases in lifetime treatment costs using the NGS could be as high as 66 percent when compared to no screening, and 12 percent when compared to traditional genotyping-based carrier screens. Also described is a robust and comprehensive decision tree model of 1 million couples representative of the United States population. Data from published literature, population surveys, and expert opinion were used to capture and reflect a complex network of medical decisions and outcomes related to carrier screening and reproductive health. The model took into account direct medical costs such as screening, diagnosis and treatment costs associated with three broad health outcomes.