Question

Question 6

Using gene editing, a researcher has created a thyroglobulin knockout mouse. This mouse will be INCAPABLE of the following except

T4 secretion into the blood
Iodine accumulation in the colloid
T3 secretion into the blood
Dimerization of iodotyrosines

Answer 1

B) Iodine accumulation in the colloid

Explanation: thyroglobulin is the protein part of the thyroid hormone T3 and T4. Knockout of the thyroglobulin would result in the prevention of combination of iodine to this protein and hence T3 and T4 would not be secreted.

As a result, thyroid hormone deficiency would result that in turn stimulate the thyroid gland to increase their production and hence more iodine would be transported to colloid in order to synthesize more thyroxine.