Deafness-intellectual disability syndrome, Martin-Probst type is characterised by severe bilateral deafness, intellectual deficit, umbilical hernia and abnormal dermatoglyphics. It has been described in three males from three generations of one family. Mild facial dysmorphism (telangiectasias, hypertelorism, dental anomalies and a wide nasal root) was also present. Short stature, pancytopaenia, microcephaly, and renal and genitourinary anomalies were present in some of the patients. The mode of transmission is X-linked recessive and the causative gene has been localised to the q1-21 region of the X chromosome.

Increased thickness of the lower lip, leading to a prominent appearance of the lower lip. The height of the vermilion of the lower lip in the midline is more than 2 SD above the mean. Alternatively, an apparently increased height of the vermilion of the lower lip in the frontal view (subjective).