Given the proximity of CERS3 to the PWS region it is highly likely that the phenotype of ARCI observed in our patient is attributable to maternal uniparental disomy of the mutated CERS3. In support of this hypothesis is the homozygosity for a novel mutation in a child of unrelated parents, the absence of other pathogenic mutations in ARCI genes, and the similarity of the phenotype to those of previous cases of CERS3‐mutated ARCI. This evidence concerns the gene CERS3 and autosomal recessive congenital ichthyosis.