CYP21A2 and congenital adrenal hyperplasia: This mechanism results in the appearance of pseudogene-gene chimeras (traditionally named “gene deletions”) usually extending from somewhere between exons 3 and 8 of CYP21A2P to the corresponding point in CYP21A2, yielding a non-functional gene in which the 5’-end corresponds to CYP21A2P and the 3’-end corresponds to CYP21A2. It is important to mention a subset of patients in which the deletion is extended into the TNXB gene resulting in a contiguous gene syndrome named CAH-X consisting in CAH and Ehlers-Danlos Syndrome (24) that should also be investigated (25).