Learn More (karyotype)

Example of a normal male karyotype, denoted 46,XY

  • 46 refers to the total number of chromosomes.
  • XY indicates a male karyotype; XX would indicate a female karyotype.

A normal human karyotype consists of 22 pairs of autosomes and two sex chromosomes. Note the similar size and striped (banding) pattern between each of the pairs. The autosomal chromosome pairs are numbered and arranged from largest to smallest. Bending and curling of the chromosomes are typically observed and do not represent an abnormality.

karyotype

Reprinted from Nussbaum RL, McInnes RR, Willard HF, eds: Thompson & Thompson Genetics in Medicine, 6 ed. Chromosomal basis of heredity, p 8. Copyright 2001, with permission from Elsevier.

Posted: 12-31-03

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