What Genotype Are Women?

By Richard Gaughan; Updated April 24, 2017
Chromosomes contain genetic information, including the instructions for building a man or woman.

The normal genetic makeup of humans consists of 23 pairs of chromosomes. Twenty-two of the 23 are autosomes -- each one of the pair looks pretty much like the opposite one in the pair. The twenty-third set of chromosomes are the sex chromosomes. There are two types of sex chromosomes: X and Y. The X and Y don't look like each other, and someone with those genes is male. Someone with two X chromosomes is female.


A person's genotype is the entire set of 23 pairs of chromosomes. The only chromosome pair that determines the sex of the individual is the XX or XY pair. So a woman can have exactly the same genotype as a man, except that she will have two X chromosomes instead of an XY chromosome. So the only distinguishing feature of a woman's genotype is the presence of two X chromosomes.

About the Author

First published in 1998, Richard Gaughan has contributed to publications such as "Photonics Spectra," "The Scientist" and other magazines. He is the author of "Accidental Genius: The World's Greatest By-Chance Discoveries." Gaughan holds a Bachelor of Science in physics from the University of Chicago.