4p16.3 region deletion
Deletion in the short arm of chromosome 4 (4p16.3 region), including at least part of the LETM1 and WHSC1 genes, is responsible for Wolf-Hirschhorn syndrome (WHS). Both LETM1 (Leucine zipper-EF-hand containing TransMembrane protein 1) as WHSC1 gene (Wolf-Hirschhorn Syndrome Candidate 1) have a role in the phenotype of Wolf-Hirschhorn syndrome. Deletions greater than 3 Mb seem to be associated with higher risk of heart defects and cleft palate. Antenatal testing is feasible when a 4p16.3 chromosome rearrangement is already identified in one parent.