PATHOLOGY

Detailed explanation-1: -X-linked recessive diseases most often occur in males. Males have only one X chromosome. A single recessive gene on that X chromosome will cause the disease. The Y chromosome is the other half of the XY gene pair in the male.

Detailed explanation-2: -In females (who have two X chromosomes), a variant would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked recessive disorders much more frequently than females.

Detailed explanation-3: -Patterns of inheritance Second, X-linked recessive traits are more commonly expressed in males than females. This is due to the fact that males possess only a single X chromosome, and therefore require only one mutated X in order to be affected.

Detailed explanation-4: -While the sex chromosomes follow the same rules, the difference in distribution puts a new spin on those rules. Females have two X chromosomes, while males only have an X and a Y. Since males only have one X, they only have one allele of each gene on the X.

Detailed explanation-5: -Fathers cannot pass X-linked recessive conditions to their sons. When a son inherits a mutated gene on the X chromosome from his mother, the genetic condition is more likely to occur. X-linked recessive conditions most often occur in males.