Each chromosome pair viewed in a karyotype appears to have its own distinct "bar code" of bands. What changes do scientists look for in a karyotype when diagnosing diseases and disorders?

A century after Down syndrome was first described ... were able to identify a supernumerary copy of chromosome 21 in karyotypes prepared from DS patients (Figure 2). Trisomy 21 is now accepted ...

The three wiggly copies of the 21st chromosome that appeared in a karyotype offered visual proof. I am grateful that my ...