This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nature of Gene Abnormalities, Subject name: Pathology
[{'content': "Genomic imprinting is seen in - \nSelect and explain. \nA. Klinefelter's syndrome, B. Down's syndrome, C. Angelman syndrome, D. Hydatidiform mole", 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Angelman syndrome o The phenomenon referred to as genomic imprinting leads to pereferential expression of an allele depending on its parental origin - HarrisonsGenomic imprintingo Human inherits two copies of each gene. i.e. two alleles, from homologous maternal and paternal chromosomes,o There is no functional difference between the genes derived from mother or the father.o But, with respect to some genes, there are functional differences between the paternal gene and maternal gene,o These differences result from an epigenetic process, called genomic imprinting,o In most cases, genomic imprinting selectively inactivates either the maternal or paternal allele.Maternal genomic imprintingo Selective inactivation of maternal allele,o Example is Angelman syndrome.Paternal genomic imprintingo Selective inactivation of Paternal allele,o Example is Prader - Willi syndrome.", 'role': 'assistant'}]