Accumulation of substantial excess body fat.

An abnormality of vibrational conductance of sound to the inner ear leading to impairment of sensory perception of sound.

A decreased magnitude of the sensory perception of sound.

A progressive form of sensorineural hearing impairment.

Incomplete formation of the cochlear partition. The scala vestibuli and scala tympani separated by the cochlear partition, except in the apical turn where the two scalae are in continuity via the helicotrema.

Mild intellectual disability is defined as an intelligence quotient (IQ) in the range of 50-69.

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.

Choroideremia (CHM) is characterized by progressive chorioretinal degeneration in affected males and milder signs in heterozygous (carrier) females. Typically, symptoms in affected males evolve from night blindness to peripheral visual field loss, with central vision preserved until late in life. Although carrier females are generally asymptomatic, signs of chorioretinal degeneration can be reliably observed with fundus autofluorescence imaging, and – after age 25 years – with careful fundus examination.

Inability to see well at night or in poor light.

An absolute or relative decrease in retinal sensitivity extending from edge (periphery) of the visual field in a concentric pattern. The visual field is the area that is perceived simultaneously by a fixating eye.

A reduction of previously attained ability to see.

Atrophy of the choroid and retinal layers of the fundus.