Five new loci (rs10937625 in STK32B (serine/threonine kinase 32B), rs17590046 in PPARGC1A [peroxisome proliferator-activated receptor gamma coactivator 1-alpha), and rs12764057, rs10822974, and rs7903491 in CTNNA3 (catenin alpha 3)] have been identified, and are significantly associated with increased risk of ET in individuals of Caucasian ancestry (9). The gene discussed is PPARGC1A; the disease is essential thrombocythemia.