Cretinism refers to severe hypothyroidism in an infant or child as a result of maternal iodine deficiency. Cystic fibrosis is an inherited disorder that causes severe damage to the lungs, digestive system and other organs in the body. Thalassemia is an genetic disease caused by mutations in the DNA of RBCs and hampers the haemoglobin production in the body. Haemophilia is a genetic condition, that is characterized by a deficiency in blood clotting. Related Theory There are two major kinds of haemophilia: hemophilia A, which is a factor VIII deficiency; and hemophilia B, which is a factor IX deficiency. People with hemophilia may bruise and bleed easily, and they may bleed a lot or for a long time after an injury.