What are sex-linked traits?

Sex-linked traits are those that are associated with genes located on the sex chromosomes, which are the X and Y chromosomes in humans and many other organisms. These traits are often observed in patterns that depend on the sex of the individual because the sex chromosomes are inherited differently compared to the autosomes (non-sex chromosomes). For example, males have one X and one Y chromosome, while females have two X chromosomes. This difference in chromosome composition can lead to specific inheritance patterns for traits linked to these chromosomes, such as color blindness or hemophilia, which are examples of X-linked recessive traits.

Traits found on autosomes are not classified as sex-linked since they are not located on the sex chromosomes. Environmental factors influencing traits do not define them as sex-linked either, as such traits may arise from a variety of influences beyond genetics. Furthermore, while certain sex-linked traits may have a more pronounced effect in males, they do not exclusively affect one sex, so stating that these traits affect only males would not accurately represent the nature of sex-linked inheritance. Therefore, the definition of sex-linked traits being associated with genes on sex chromosomes is the most accurate and encompasses the fundamental principles of genetics.