21st July 2023

A 10-year-old boy presents to the paediatric emergency department with a 1-week history of abdominal pain

A 10-year-old boy presents to the paediatric emergency department with a 1-week history of abdominal pain associated with bloating and occasional PR bleeding. He has no past medical history and takes no regular medications. A family history is unable to be obtained as he is adopted. Examination reveals mild abdominal tenderness on palpation of the left iliac fossa without features of peritonism. A PR exam is unremarkable. He undergoes an inpatient colonoscopy which reveals over 100 polyps within the colon.

Given the most likely diagnosis, what gene mutation is most likely to be found in this patient?

Select the SINGLE most appropriate option from the list below. Select ONE option only.