This can lead to a fertilised egg with two free 21 chromosomes and a translocated chromosome. This child will subsequently have Down’s syndrome. The chromosomes that may be Apollo 11 50th anniversary neil armstrong michael collins buzz aldrin signatures shirt concerned are numbers thirteen, 14, 15, 21, 22. Most people with Down’s syndrome have this type. This makes it different from different genetic situations, comparable to cystic fibrosis or sickle cell disease, whose inheritance can be traced by way of families. Round four% of people with Down’s syndrome have this kind.