Chromosome human, numbering, staining pattern

Figure 26-15 (A) Numbering and staining patterns (G-banding) of human chromosomes. The horizontal line marks the centromeres. Chromosomes 13,14,15, 21, and 22 have nucleolar organizers located at the constrictions in their short arms. From Alberts et al.297 Adapted from U. Franke.298 (B) Map of genetic defects identified in X chromosomes by 1995. From McKusick and Amberger.294...

Chromosomes from any one individual species, when stained with special dyes, give a consistent and unique pattern, like a bar code. This is a very reproducible pattern, and the bands in human chromosomes have therefore been numbered. 

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