A 60-year-old man is brought to the emergency with generalized tonic-clonic seizure. There was no history of similar episodes in the past. There is no h/o any other medical illness. He is given lorazepam 2 mg which leads to cessation of seizure activity. Which of the following is the least likely cause of seizure in this patient?

In individuals ->35 years age, the most likely causes of new-onset seizures include alcohol withdrawal, cerebrovascular disease, brain tumor, autoantibodies, Alzheimer disease or other neurodegenerative disease, and a range of metabolic disorders. These disorders can include either hyper/ hypoglycemia, uremia, hepatic failure, and electrolyte abnormalities or acid-base disorders. The genetic disorders typically present in childhood and rarely after the age of 18.