Why is it more difficult to test for cystic fibrosis than it is to test for sickle-cell anemia?

More tests needed: Sickle cell disease is somewhat easier to diagnose. It is a genetic blood disorder caused by abnormal hemoglobin which tend to aggregate after unloading oxygen forming long, rod-like strictures that cause the red cells to assume a sickle shape. These sickle red cells cannot squeeze through small blood vessel and cause anoxia in organs.Cystic fibrosis is more complex to define resulting from failure to remethylate and shut off MUC5ac, an oncofetal gene which produces mucin in the fetus. Chest X ray and lung function tests may indicate problems from excess mucin.