This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Types of Genetic Disorders, Subject name: Pediatrics
[{'content': 'Different mutations in the same genetic locus causing similar or identical phenotype is? \nSelect and explain. \nA. Phenotypic heterogeneity, B. Allelic heterogeneity, C. Locus heterogeneity, D. Non-allelic heterogeneity', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Allelic heterogeneity Different mutations in the same genetic locus can cause an identical or similar phenotype. eg- different mutations of the b-globin locus- b-thalassemia Phenotypic Heterogeneity When more than one phenotype is caused by allelic mutations e.g. Identical mutations in the FGFR2 gene- Crouzon syndrome or Pfeiffer syndrome Locus or Non-allelic Heterogeneity Similar disease phenotype results from mutations at different genetic loci. eg- osteogenesis imperfecta- mutations in COL1A1 or COL 1A2: located on different chromosomes', 'role': 'assistant'}]