During the study, the child was found to have trisomy on the 21st pair of chromosomes (Down’s disease).

During the study, the child was found to have trisomy on the 21st pair of chromosomes (Down’s disease). Explain which method was used to determine the cause of the disease and what kind of mutation it is associated with.

1) the cause of the disease was established using the cytogenetic method;
2) the disease (Down syndrome) is caused by a genomic mutation – a non-multiple change in the number of chromosomes (heteroploidy).