Whereas amorphic variants of IKBKG are lethal in males, hypomorphic NEMO deficiency results in X-linked hypohidrotic ectodermal dysplasia with immunodeficiency (EDA-ID) composed of hypogammaglobulinemia, susceptibility to infections, ectodermal dysplasia, and various degrees of defective T- and B-cell function [9–12]. The gene discussed is IKBKG; the disease is X-linked hypohidrotic ectodermal dysplasia.