Medical Genetics 1 Down syndrome A, A Brief History The formal story began in 1866 when a physician named John Langdon Down published an essay in England in which he described a set of children with common features who were distinct from other children With mental retardationMedical Genetics 1. Down syndrome A. A Brief History The formal story began in 1866, when a physician named John Langdon Down published an essay in England in which he described a set of children with common features who were distinct from other children with mental retardation