Heterozygous Kcnk16 L114P caused almost complete neonatal lethality in the B6 background but only hyperglycemia in the B6:CD-1 background, whereas homozygous Kcnk16 L114P led to neonatal lethality in the B6:CD-1 mice. The gene discussed is KCNK16; the disease is Hyperglycemia.