What is a Supermale- XYY Syndrome?

A supermale is an individual containing XYY sex chromosomes.

In similar words, a supermale is an individual that has XYY syndrome; he has an extra Y sex chromosome in his genes.

A Normal Chrosomal set

A healthy individual has 2 sex chromosomes. A normal healthy female has 2 sex chromosomes, 2 X chromosomes, for an XX set of sex chromosomes. A normal healthy male has 2 sex chromosomes, an X chromosome and a Y chromosome, for an XY set of sex chromosomes.

Below is a karyotype of a normal and healthy male individual.

The sex chromosomes are the last pair of chromosomes, for which you can see an X and Y under the pair.

You can see that in a normal, healthy male individual, there are 2 sex chromosomes present, an XY set.

Supermale- XYY syndrome

However, not all males are born with an XY set of chromosomes. Some males are born with 3 sex chromosomes, 1 X chromosomes and 2 Y chromosomes, for an XYY set of sex chromosomes.

Below is the karyotype of an individual with XYY syndrome:

You can see the extra Y chromosome present in the sex chromosomes.

Symptoms of (Supermale) XYY Syndrome

The only symptoms that may result from being a supermale (XYY syndrome) are possible learning disabilities.

Originally, supermales were thought to be extra aggressive, even to the point of being violent, but this has since been disproven. Aggressive and violent tendencies do not occur consistently in supermales for it to be a proven trait.

Incidence of Supermales

The incidence of supermales, or males having XYY syndrome, is 1 out of 1000 live births.

Related Resources

Down's Syndrome

Edward's Syndrome

Patau's Syndrome

Turner's Syndrome

Klinefelter's Syndrome

Superfemale- XXX Syndrome