TSHR and thyrotoxicosis: These 2 TSHR intron 1 associations were unrelated to each other by linkage disequilibrium (LD) (r2 < 0.05), and neither association showed any phenotypic crossover (i.e., the thyrotoxicosis association showed no relationship to hypothyroid risk and vice versa), suggesting potentially distinct mechanisms or context specificity underlying these 2 intronic associations.