Answer:
One of the most common chromosomal disorders is Down syndrome. Down syndrome happens when abnormal cell division results in extra genetic material from chromosome 21, too few chromosomes, or part of a chromosome may be missing. The difficulties of Down syndrome include hearing and vision weakness, weak auditory memory, fine motor skill impairment, short attention span with distractibility. Having Down syndrome can increase the risk of developing Alzheimer's disease. Having down syndrome can be associated with other health conditions such as ear infections, dental problems, endocrine problems, and seizures.