• variable penetrance, usually of digits 2 and 3 or 3 and 4, more rarely 2, 3 and 4; fusion of 2, 3 and 4 is more frequently seen on the hind paw than the fore paws

• within 1 month of birth

• thin semicircular canals

• development of excessive mesenchymal tissue followed by collapse of endolymphatic space and degeneration of membraneous labyrinth

• variable penetrance

• usually of digits 2 and 3 or 3 and 4

• thin long bones

• synostosis of phalanges

• variable penetrance

• no discernible auditory brainstem responses (ABR) to maximum output stimuli at 99 dB

• profoundly deaf at 2-3 month of age