Idiopathic thrombocytopenic purpura (ITP) Idiopathic thrombocytopenic purpura (ITP) is a bleeding disorder in which the immune system destroys platelets, which are necessary for normal blood clotting. People with the disease have too few platelets in the blood. ITP is sometimes called immune thrombocytopenic purpura or simply, immune thrombocytopenia.
sex-linked disorder - any disease or abnormality that is determined by the sex hormones; hemophilia is determined by a gene defect on an X chromosome. bleeder's disease, haemophilia, hemophilia - congenital tendency to uncontrolled bleeding; usually affects males and is transmitted from mother to son.
Besides genes that determine sex, sex chromosomes carry many genes for traits unrelated to sex. X-linked gene is any gene located on the X chromosome that are missing on the Y chromosome. X-linked alleles are designated as superscripts to X chromosome. Newly discovered mutant male fruit fly had white eyes.