TGM1 and ichthyosis: In more than 50% of the patients, LI is caused by mutations in TGM1, however, TGM1 mutations have also been reported to cause CIE (Becker et al., 2003; Herman et al., 2009), as well as other subtypes of ARCI, such as bathing suit ichthyosis (BSI) and self‐improving ichthyosis (SII) (Hackett, Fitzgerald, Watson, Hol, & Irvine, 2010; Raghunath et al., 2003).