However, there are only five cases of ichthyosis caused by UPD involving CERS3 (2), ABCA12 (2), and SPINK5 (1) (Castiglia et al., 2009; Numata et al., 2014; Shibata et al., 2015; Polubothu et al., 2018; Muthusamy et al., 2020). The gene discussed is ABCA12; the disease is ichthyosis.