GPX4 and obesity due to melanocortin 4 receptor deficiency: Although the GPX4 rs713041 [C/T] variant, located in the 3’UTR, the mRNA region important for selenocysteine insertion, was not investigated with obesity, this polymorphism showed risk modulation for diabetic retinopathy and cardiovascular autonomic neuropathy in patients with type 1 diabetes [37,38].