The inheritable characters that are determined by a gene located on the X-chromosome is

The inheritable characters that are determined by a gene located on the X-chromosome are referred to as sex-linked. This means that the gene responsible for a particular trait is located on the X chromosome, which is one of the two sex chromosomes (the other being the Y chromosome). In humans, females have two X chromosomes (XX) and males have one X and one Y chromosome (XY). Because females have two copies of the X chromosome, they have two copies of any gene located on the X chromosome. This means that if one copy of a gene on the X chromosome is faulty, they have a second, normal copy to compensate. In contrast, males only have one copy of the X chromosome, so if a gene on the X chromosome is faulty, they do not have a second, normal copy to compensate. This can result in certain traits being more commonly seen in males. Sex-linked traits can be either dominant or recessive. A dominant trait is one that will be expressed if a person has at least one copy of the dominant allele (version of a gene). A recessive trait is only expressed if a person has two copies of the recessive allele. In the case of sex-linked traits, because males only have one X chromosome, a dominant trait will always be expressed, while a recessive trait will only be expressed if both copies of the X chromosome carry the recessive allele.