 Patients taking thyroid hormone replacement after thyroid removal surgery often report feeling differently than they did prior to taking thyroid hormone. The symptoms can include fatigue, worsening mood or subjective brain fog where the patient feels like their thinking is just not as sharp as it was previously. Multiple studies have found that patients taking thyroid hormone replacement have a diminished quality of life compared to matched controls. Previous studies have suggested that the type of deiodinase DIO polymorphism a patient has, which is responsible for converting the thyroid hormone T4 into the more biologically active T3, may contribute to their overall cognition and sense of well-being. The Investigators aim to determine if the type of deiodinase polymorphism a patient has contributes to the patients cognition and overall sense of well-being after surgery and thyroid hormone replacement. 