X-linked recessive inheritance: These diseases arise from an error on the X chromasome, which causes disease only when there is no corresponding paired X chromasome with a good gene. However, since men are XY a man with the bad gene on the X chromasome must get the disease, because there is no second X chromasome. Since women are XX, they usually have a second good X chromasome which suppresses the bad X gene, leaving them disease-free, but as carriers. The following patterns of inheritance are typical:
Gender bias: Typically, males are the ones who get the disease, whereas females are carriers. Men cannot be carriers because they cannot have a bad X chromasome gene without getting the disease. Women cannot get the disease, because they typically have a second good X chromasome. However, in the rare case of a daughter of an affected father and a carrier mother, then the daughter might have two bad X genes and get the disease itself (like an autosomal recessive disease).
Father to son transmission: 0% chance of disease and 100% chance of disease-free unless the mother is also a carrier (males always get their single X from the mother not father and cannot get a bad gene from the father), 0% chance of carrier (males cannot be carriers).
Father to daughter transmission: 0% chance of disease (females can only be carriers), 100% chance the female child is a carrier (because the father gives a bad X gene as there is only the bad one to give). If the mother is also a carrier, the female can be fully afflicted with the rare double-recessive female version of the disease.
Mother (carrier) to son transmission: 50% chance of disease, 50% chance disease-free, 0% chance of carrier (males cannot be carriers).
Mother to daughter:: 0% chance of disease (females can only be carriers), 50% chance of female carrier, 50% chance neither affected nor carrier.
Other children: If a couple has one (male) child with the disease, what are the odds for another child having it. Usually this means the mother is a carrier, because the father cannot transmit the disease to a child (and the father would probably have noticable disease). So the risk for a second child of the same couple is probably the mother-to-son transmission risk, 50% chance of disease, and a female child cannot have the disease but has a 50% chance of being a carrier.
Mild disease in female carriers: Female carriers can have a mild form of disease, because they have a bad gene on one of their two X chromasomes, and a good gene on the other. If the disease is not totally recessive, a partial disease can result even though the woman has one good gene. In other words, if the second gene copy is not a good enough "backup", a partial level of mild disease can still result in carriers. However, most X-linked recessive diseases have symptom-free female carriers.
Sporadic cases: A genetic disease that occurs when neither parent has any genetic defect is called a sporadic genetic disease. These cases arise via random genetic mutations in the DNA. A sporadic mutation can be the cause of an x-linked recessive disease (whereas it is unlikely for an autosomal recessive disorder) because only a single mutation is required (in males) to cause the disease. Females can also become carriers owing to random mutations.
source:
http://www.wrongdiagnosis.com/genetics/xrec.htm 
