This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
[{'content': 'Single gene defect causing multiple unrelated problems is known as: \nSelect and explain. \nA. Pleiotropism, B. Pseudodominance, C. Penetrance, D. Anticipation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Pleiotropism refers to the phenomenon in which a single mutant allele having widespread effects or expression in different tissues or organ systems. Eg is Marfans syndrome caused by a mutation in fibrillin gene causing multiple manifestations. Penetrance refers to the propoion of individuals with a paicular genotype that express the same phenotype. Penetrance is said to be complete when 100% of mutant individuals express the phenotype. Penetrance is incomplete when some mutant individuals do not express the phenotype. Ref: Tsaic A.C., Manchester D.K., Elias E.R. (2012). Chapter 37. Genetics & Dysmorphology. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.', 'role': 'assistant'}]