A U wave as seen on ECG. An electrocardiogram of an 18-year-old man showing U waves, most evident in lead V3. The U wave is a wave on an electrocardiogram that is not always seen. It is typically small, and, by definition, follows the T wave. U waves are thought to represent repolarization of the papillary muscles or Purkinje fibers.
HCP is caused by mutations in the CPOX gene, which codes for the enzyme coproporphyrinogen oxidase. This enzyme is responsible for the sixth step in the heme biosynthetic pathway, converting coproporphyrinogen III to protoporphyrinogen IX.
Hereditary Cancer[edit] Patients may be referred to a genetic counselor based on their cancer diagnosis, or a strong family history of cancer. It is estimated that only 5-10% of cancers are hereditary, meaning that these cancers are due to a gene mutation that has been passed down in the family.