After step-wise bioinformatics WES analysis and subsequent prioritization using the HPO term “Palmoplantar keratoderma” (HP:0000982) (Table S1), a novel homozygous variant in the PERP gene (NM_022121.5) was identified: c.153C>A, p.(Cys51Ter). The gene discussed is PERP; the disease is hereditary palmoplantar keratoderma.