Non-homologous end joiningDownloads

A 45-year-old woman presents with heavy menstrual bleeding between her periods. The patient also complains of experiencing an irregular menstrual cycle, weight loss, bloating, and constipation. She has had 3 uncomplicated pregnancies, all of which ended with normal vaginal deliveries at term. She has never taken oral contraception, and she does not take any medication at the time of presentation. She has no family history of any gynecological malignancy; however, her grandfather and mother had colon cancer that was diagnosed before they turned 50. On physical examination, the patient appears pale. Gynecological examination reveals a bloody cervical discharge and slight uterine enlargement. Endometrial biopsy reveals endometrial adenocarcinoma. Colonoscopy reveals several polyps located in the ascending colon, which are shown to be adenocarcinomas on histological evaluation. Which of the following mechanisms of DNA repair is likely to be disrupted in this patient?

A 29-year-old man comes to the emergency department because of progressively worsening fatigue and shortness of breath for the past 2 weeks. His only medication is insulin. Examination shows elevated jugular venous distention and coarse crackles in both lungs. Despite appropriate life-saving measures, he dies. Gross examination of the heart at autopsy shows concentrically thickened myocardium and microscopic examination shows large cardiomyocytes with intracellular iron granules. Examination of the spinal cord shows atrophy of the lateral corticospinal tracts, spinocerebellar tracts, and dorsal columns. Which of the following is the most likely underlying cause of this patient's condition?