A 65 year old male who is a former professional wrestler awakened one morning wi

A 65 year old male who is a former professional wrestler awakened one morning with severe back pain in his middle and lower back. Initially, he was suspecting that his back pain was due to the couch that his wife had forced him to sleep on after a huge argument about buying the wrong brand of paper towels. He attempted to “tough it out,” going to his part-time job as a plumber. However, his pain began to worsen as the day progressed, with little to no improvement despite taking a friend’s Naproxen Sodium and Aleve.
Concerned about possibly tearing a muscle in his back (he had done so many years ago when landing on his back wrong after attempting a somersault move on an opponent in the ring), he went to an orthopedic surgeon. When asked about a family history of similar issues, however, he remembered that his grandfather, father, and at least 3 of his brothers also suffered from similar issues. Given this new history, the orthopedic surgeon performed a radiograph of his spine, which was revealing of a “bamboo spine” pattern which prompted further workup. Given the strong family history of back pain in males, HLA-B27 testing was performed and signified a “positive” result. All of this testing was diagnostic of ankylosing spondylitis.
Please answer the following questions:
How does the immune system mitigate itself to prevent the onset of autoimmune diseases?
How do genetics and epigenetics play a role in the onset of autoimmune disease?
What other diseases would occur co-incidently with ankylosing spondylitis, based on the mutation associated with it?
Please include an opening paragraph on what ankylosing spondylitis is, and a paragraph answering each question with at least 1 reference and in text citation per paragraph.