In non-obese diabetic (NOD) mice, up-regulation of miR-29a, b and c caused pancreatic β-cell death via suppression of the myeloid cell leukemia 1 (MCL-1) gene, an essential member of the pro-survival BCL-2 family genes, and marked the first stage of type 1 DM (T1DM) [15]. The gene discussed is MCL1; the disease is type 1 diabetes mellitus.