Accelerating Gene Discovery by Phenotyping Whole-Genome Sequenced Multi-mutation Strains and Using the Sequence Kernel Association Test (SKAT).

Forward genetic screens represent powerful, unbiased approaches to uncover novel components in any biological process. Such screens suffer from a major bottleneck, however, namely the cloning of corresponding genes causing the phenotypic variation. Reverse genetic screens have been employed as a way to circumvent this issue, but can often be limited in scope. Here we demonstrate an innovative approach to gene discovery. Using C. elegans as a model system, we used a whole-genome sequenced multi-mutation library, from the Million Mutation Project, together with the Sequence Kernel Association Test (SKAT), to rapidly screen for and identify genes associated with a phenotype of interest, namely defects in dye-filling of ciliated sensory neurons. Such anomalies in dye-filling are often associated with the disruption of cilia, organelles which in humans are implicated in sensory physiology (including vision, smell and hearing), development and disease. Beyond identifying several well characterised dye-filling genes, our approach uncovered three genes not previously linked to ciliated sensory neuron development or function. From these putative novel dye-filling genes, we confirmed the involvement of BGNT-1.1 in ciliated sensory neuron function and morphogenesis. BGNT-1.1 functions at the trans-Golgi network of sheath cells (glia) to influence dye-filling and cilium length, in a cell non-autonomous manner. Notably, BGNT-1.1 is the orthologue of human B3GNT1/B4GAT1, a glycosyltransferase associated with Walker-Warburg syndrome (WWS). WWS is a multigenic disorder characterised by muscular dystrophy as well as brain and eye anomalies. Together, our work unveils an effective and innovative approach to gene discovery, and provides the first evidence that B3GNT1-associated Walker-Warburg syndrome may be considered a ciliopathy.

Anticoagulation stewardship: Improving adherence to clinical guidelines and reducing overuse of venous thromboembolism prophylaxis in hospitalized medical patients.

Adherence to guideline recommendations for venous thromboembolism prophylaxis (VTE) in hospitalized medical patients is suboptimal despite national policies and institutional interventions. The aim of this quality improvement project was to improve adherence to guidelines and decrease the overuse of VTE prophylaxis in order to reduce the institutional cost for heparins. A multidisciplinary anticoagulation stewardship program (ACSP) using the audit and feedback strategy was implemented on the medicine inpatient units at a teaching hospital in Canada. The primary outcome measure was a comparison, pre and post introduction of the ACSP, of the costs per 6-month period for prophylactic dose enoxaparin and unfractionated heparin on the medicine units. The balancing measures were the 90-day VTE rate and major bleeding rate during the hospitalization. Six months after the implementation of the ACSP, the cost was decreased by >50 % without any observed negative impact on patient safety. This study demonstrates the potential for anticoagulation stewardship programs to optimize the use of VTE prophylaxis and reduce the associated costs and risks.