A: The function of the cartilaginous rings of the trachea is to stabilize the trachea and keep it rigid while allowing the trachea to expand and lengthen when the person breathes. If the trachea was not supported in this way, it would simply collapse because of the pressure of the chest.
HCM remains the most common cardiovascular genetic disorder, occurring in at least 1 in 500 people in the general population. 7 HCM is a primary inherited disorder of the myocardium characterized by hypertrophy, usually of the left ventricle, in the absence of other loading conditions such as hypertension.
CJD is the most common of the known human TSEs. Other human TSEs include kuru, fatal familial insomnia (FFI), and Gerstmann-Straussler-Scheinker disease (GSS). Kuru was identified in people of an isolated tribe in Papua New Guinea and has now almost disappeared. This is by far the most common type of CJD and accounts for at least 85 percent of cases. 2  In hereditary CJD, the person has a family history of the disease and/or tests positive for a genetic mutation associated with CJD. About 5 to 10 percent of cases of CJD in the United States are hereditary.