In 2020, Messina et al. performed whole-exome sequencing for 240 unrelated CHH patients mostly of European origin and identified four apparently pathogenic variants in NDNF (NM_024574.4) (p. Lys62*, p. Tyr128Thrfs*55, p. Trp469*, and p. Thr201Ser) in four patients2. This evidence concerns the gene NDNF and cartilage-hair hypoplasia.