 Mutations in IKK-α in humans have been linked to lethal fetal malformations.The phenotype of these mutant fetuses is similar to the mouse IKK-α null phenotype, and is characterized by shiny, thickened skin and truncated limbs.Decreased IKK-α activity has been reported in a large percentage of human squamous cell carcinomas, and restoring IKK-α in mouse models of skin cancer has been shown to have an anti-tumorigenic effect.