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.
Classical PKU is caused by a deficiency of the enzyme phenylalanine hydroxylase (PAH). Over 70 different mutations on the PAH gene found on Chromosome 12 have been found to cause the almost complete absence of PAH as seen in PKU patients.revalence. The incidence of PKU is highly variable in different populations. Many PAH gene mutations are thought to be Celtic in origin, this is supported by high frequencies of PKU in the Irish and in the Scottish, and for example an incidence of 1/4500 is seen in the Irish.