The FAM134B gene encodes a receptor protein that is anchored to the endoplasmic reticulum. This receptor is responsible for autophagy of the endoplasmic reticulum by binding to the autophagy modifiers LC3 and GABARAP. It is believed that FAM134B may be required for the long-term survival of certain cells, in particular, the nociceptive and autonomic ganglion neurons. This is reinforced by studies of the mouse ortholog gene as Fam134b disruption in mice has been shown to lead to the expansion of the endoplasmic reticulum, sensitize cells to stress-induced apoptotic death and result in the degeneration of sensory neurons.
Mutations in the FAM134B gene have been associated with Hereditary Sensory and Autonomic Neuropathy, Type IIB (HSAN2B), a neurologic disorder characterized by an impaired sensory perception of pain, temperature and touch in the distal extremities.