is a genetic disorder caused by a recessive allele on the
X chromosome

Hemophilia

Explanation:

This is a disorder in which a blood coagulation factor is missing from the blood, so if the person with the disorder gets even a small injury, he'll bleed a lot due to absence of proper blood coagulation.

It's more common in males than females because females have two X chromosomes. If they have one recessive allelle on one X chromosome, while the other has the dominant allele, they're going to be asyptomatic carriers of the recessive allele.

However, since males have only one X chromosome, having the recessive allele means that they'll suffer from hemophilia. There's no chance of them being just carriers unlike the females.

This test can be used to determine if you have antibodies related to certain infectious conditions. Antibodies are proteins that your body produces in response to harmful substances called antigens. An ELISA test may be used to diagnose: HIV, which causes AIDS.