cytogenetic map

location Cygnus X-1 alongside images of it taken by NuSTAR and an earlier X-ray telescope

Cytogenetic maps of the human chromosomes.

A cytogenetic map is the visual appearance of a chromosome when stained and examined under a microscope. Particularly important are visually distinct regions, called light and dark bands, which give each of the chromosomes a unique appearance. This feature allows a person's chromosomes to be studied in a clinical test known as a karyotype, which allows scientists to look for chromosomal alterations.