On lumpers and splitters, or the nosology of genetic disease.

Dwarfism Ellis-Van Creveld Syndrome/genetics Genetic Diseases, Inborn/classification,diagnosis Genetics, Medical Genotype Humans Inbreeding Intestinal Diseases/genetics Mucopolysaccharidoses/genetics Peripheral Nervous System Diseases/genetics Peutz-Jeghers Syndrome/genetics Phenotype Polyps/genetics Retinitis Pigmentosa/genetics Terminology as Topic