Most heart attacks happen when a clot in the coronary artery blocks the supply of blood and oxygen to the heart. Often this leads to an irregular heartbeat-called an arrhythmia-that causes a severe decrease in the pumping function of the heart.
The abnormal FIG-ROS fusion protein has constitutively active kinase activity that causes oncogenic transformation (a transformation from normal cells to cancer cells). Chromosomal inversion s: reversing the orientation of a chromosomal segment.
Because most proto-oncogenes are basic to animal life, they have been highly conserved over eons of evolutionary time. Conversion, or activation, of a proto-oncogene into an oncogene generally involves a gain-of-function mutation. At least three mechanisms can produce oncogenes from the corresponding proto-oncogenes. 1  Point mutations in a proto-oncogene that result in a constitutively acting protein product. 2  Localized reduplication (gene amplification) of a DNA segment that includes a proto-oncogene, leading to overexpression of the encoded protein.