Retrognathic mandible has a multifactorial etiology so further studies are required to investigate other genes that could be involved in the cause of retrognathic mandible and to include subjects with different ethnicity in the sample who are also having features other than mandibular retrognathia like hearing loss, abnormal pinnae, ectrodactyly, cleft palate, developmental delay and abnormal teeth to determine the contribution of DLX6 gene variations in mandibular deficiency. The gene discussed is DLX6; the disease is Global developmental delay.