Natural Progression of Canine Glycogen Storage Disease Type IIIa.

As a clinical biochemical geneticist and a director of the Duke Biochemical Genetics laboratory, my research interests are focused on improving laboratory diagnostics for rare inherited disorders of metabolism. I am actively involved in the development of assays using mass spectrometry and other analytical techniques. My current research on biomarkers for lysosomal storage disorders, such as Fabry and Pompe disease and the mucopolysaccharidoses includes monitoring the response to novel therapies in patients. I also have an interest in neurometabolic disorders such as the creatine deficiency syndromes and sulfite oxidase and molybdenum cofactors. These disorders can be diagnosed using liquid chromatography-tandem mass spectrometric assays that measure biomarkers in urine. Guanidinoacetate methyltransferase deficiency is a disorder that can be detected in the newborn period and is amenable to dietary therapy, and is thus a good candidate for newborn screening.

RESEARCH INTERESTS

A multidisciplinary approach to care of individuals with genetic disorders in conjunction with clinical and bench research that contributes to:
1) An understanding of the natural history and delineation of long term complications of genetic disorders  with a special focus on liver Glycogen storage disorders, lysosomal disorders with a special focus on Pompe disease, Down syndrome and hypophosphatasia
2) ) The development of new therapies such as AAV gene therapy, enzyme therapy, small molecule and other approaches for genetic disorders through translational research

3) The development and execution of large multicenter trials to confirm safety and efficacy of potential therapies
4) Role of antibodies/immune response in patients on therapeutic proteins and AAV gene therapy

. Glycogen Storage Disease (GSD): We are actively following subjects with all types of Glycogen Storage Disease, with particular emphasis on types I, II, III, IV, VI and IX. The goal of the treatment team is to better determine the clinical phenotype and long term complications of these diseases. Attention to disease manifestations observed in adulthood, such as adenomas and risk for HCC, is of paramount importance in monitoring and treating these chronic illnesses. We are establishing clinical algorithms for managing adenomas, and the overall management of these patients including cardiac, bone, muscle and liver issues. A special focus is biomarker discovery, an Omics approach including metabolomics and immune phenotyping. We are working on AAV gene therapy for several hepatic GSDs

.Lysosomal Storage Disease: The Duke Lysosomal Storage Disease (LSD) treatment center follows and treats patients with Pompe, Gaucher, Fabry, Mucopolysaccharidosis, Niemann Pick, LAL-D and other LSD's. The Duke Metabolism Clinical Research Team is exploring many aspects of enzyme replacement therapy (ERT), including impact on different systems, differential response, and long term effects. Other symptomatic and treatment interventions for this category of diseases are also being explored in the context of clinical care.

. Pompe Disease: The care team has extensive experience in the care of infants and adults with Pompe disease and was instrumental in conducting clinical trials and the bench to bedside work that led to the 2006 FDA approval of alglucosidase alfa, the first treatment for this devastating disease. We are currently focusing on role of antibodies/immune response on patient outcome and role of immune modulation/immune suppression as an adjunct to ERT. Our team is also working on AAV gene therapy for Pompe disease. A focus is on newborn screening (NBS) and understanding the clinical phenotype and management approaches for babies identified via NBS

.  Hypophosphatasia: We follow a large cohort of patients with HPP. The goal is to understand the features of the disease beyond bone disease, development of biomarkers, role of ERT and immune responses in HPP

. Neuromuscular disorders: We are collaborating with neurologists, cardiologists and neuromuscular physicians to serve as a treatment site for clinical trials in these diseases. We are currently involved in trials of DMD and are working closely on setting up collaborations for studies in SMA.

My overall research interests are finding effective treatment for human glycogen storage diseases (GSDs) and other inherited metabolic disorders. My current research focuses on identification of novel therapeutic targets and development of effective therapies for GSD II (Pompe disease), GSD III (Cori disease), and GSD IV (Andersen disease) using cellular and animal disease models. The main therapeutic approaches we are using in our pre-clinical studies include protein/enzyme therapy, AAV-mediated gene therapy, and substrate reduction therapy with small molecule drugs.