Question

A child suffering from Down’s syndrome was carefully examined. There were three 21 chromosomes in the patient.The sequence of all genes and alleles present on two of the three 21st chromosomes were an exact match with the patient’s mother while third one was an exact match with the father. This is due to, which of the following faulty process?A child suffering from Down’s syndrome was carefully examined. There were three 21 chromosomes in the patient.The sequence of all genes and alleles present on two of the three 21st chromosomes were an exact match with the patient’s mother while third one was an exact match with the father. This is due to, which of the following faulty process?​

Answer 1

Aneupolyploidy is due to non disjunction of homologous chromosome pair so that one gamete has extra chromosome(N+1) and other gamete is chromosome deficient (N-1). Here the condition is becoz of hyperaneupolyploidy An extra 21st chromosome is present in mother’s gamete and the father’s gamete is normal