Confidence votes 11. According to Wikipedia, the width of the Atlantic Ocean at its narrowest point is 2,848 kilometers (1,770 mi) between Brazil and Sierra Leone.
What causes PNH? It is not fully understood why people develop PNH. Inside the bone marrow, blood cells are made by stem cells (the seed cells of the marrow). PNH occurs due to a change (or mutation) in a gene in one of the stem cells in the bone marrow. This mutation happens in a gene called PIG-A and the cells made by this stem cell lack certain proteins on their surface making them âweakerâ than normal blood cells.
What causes hemolytic disease of the newborn (HDN)? HDN most frequently occurs when an Rh negative mother has a baby with an Rh positive father. When the baby's Rh factor is positive, like the father's, problems can develop if the baby's red blood cells cross to the Rh negative mother. This usually happens at delivery when the placenta detaches.