The RNA binding proteins Lin28a/b inhibit the synthesis of let-7; however, the tissue-specific loss of Lin28a or overexpression of let-7 suppresses IGF1R, insulin receptor (INSR), and insulin receptor substrate 2 (IRS2) of the insulin- PI3K-mTOR pathway which leads to insulin resistance and impaired glucose tolerance. The gene discussed is INSR; the disease is Impaired glucose tolerance.