Holandric genes are genes that are located on the Y chromosome, which is one of the two sex chromosomes in humans (the other being the X chromosome).

Here's what makes holandric genes special:

* Exclusively inherited from father to son: Since only males possess a Y chromosome, holandric genes are passed directly from father to son. Females do not receive these genes.

* Few in number: The Y chromosome is much smaller than the X chromosome and contains relatively few genes.

* Linked to male sex determination: Some holandric genes play a critical role in male development, including the SRY gene which initiates the development of testes.

Examples of holandric genes:

* SRY gene: This gene triggers the development of testes, ultimately determining male sex.

* Genes involved in sperm production: Some holandric genes are responsible for the development and functioning of sperm cells.

Important Note: While holandric genes are exclusively passed from father to son, they are not the only genes that influence male characteristics. Many genes on other chromosomes also play a role in male development and function.

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