Ellen Sidransky is an American pediatrician and clinical geneticist in the Medical Genetics Branch of the National Human Genome Research Institute.She is chief of the Molecular Neurogenetics Section and a pediatrician and clinical geneticist in the Medical Genetics Branch of the National Human Genome Research Institute.She led two large international collaborative studies regarding the genetics of Parkinson's disease and dementia with Lewy bodies.Focusing on GD, the group is poised to investigate the intricate relationships between clinical manifestations, metabolic defects and molecular mechanisms, and to tackle the challenge of identifying genetic modifiers.Although GD is classically divided into three types, the section's research has shown that there is actually a continuum of manifestation, and they have uncovered several unexpected phenotypes.