Our case is the second report of EFNB1 duplication associated with CDH in a male patient, supporting its implication sensitive to gene dosage in diaphragm development.
Although the clinical phenotypes of the patients were not highly suggestive of a phenotype-genotype correlation, the two female patients were diagnosed with diaphragmatic hernia harbouring putative ephrin-B1 truncating mutations.
Our cases represent the first in which CDH has been confirmed in males with mutations in EFNB1, highlighting an important role for signalling by ephrin-B1 in the development of the diaphragm.