In an agreement with the phenotypic heterogeneity, biallelic pathogenic variants in 14 genes, namely ABCA12 (OMIM 607800), ALOX12B (OMIM 603741), ALOXE3 (OMIM 607206), CERS3 (OMIM 615276), CYP4F22 (OMIM 611495), CSTA (OMIM 184600), LIPN (OMIM 613924), NIPAL4 (OMIM 609383), PNPLA1 (OMIM 612121), POMP (OMIM 613386), SLC27A4 (OMIM 604194), ST14 (OMIM 606797), SULT2B1 (OMIM 604125), and TGM1 (OMIM 190195), account for about 85% of nonsyndromic ARCI cases [4]. This evidence concerns the gene ALOX12B and autosomal recessive congenital ichthyosis.