Table 1.

Clinical and electrophysiologic findings of clinically affected persons of the families H9, H19 and L21

ID in pedigree, gender	Age of onset (years)	Age at examination	Clinical features	EMG findings
H09-III-1, F	30 years	50 years	Distal atrophy and paresis arms (MRC grade 3) and legs (MRC 1–2). Weakness quadriceps MRC 4. Flat feet. Distal sensory disturbances arms and legs. Impaired joint position sense hallux, absent vibration sense of the legs Areflexia.	Left ulnar MNCVa forearm 43 m/s (ADM)b; right ulnar MNCV forearm 41 m/s. No CMAPsc recordable of median (APB)d, peroneal (EDB)e and tibial (AHB)f nerves. No SNAPsg recordable of right median (2nd finger), left ulnar (5th finger) and right sural (lateral malleolus) nerves. Signs of denervation and reinnervation in predominantly distal leg and arm muscles.Conclusion: severe axonal sensorimotor polyneuropathy.
H09-IV, F (index)	unknown	26 years	Calf hypertrophy. Paresis anterior tibial and peroneal muscles (MRC 4). Pes cavus. Decreased vibration sense hallux. Absent Achilles tendon jerks.	Right median MNCV forearm 39 m/s, left ulnar MNCV forearm 52 m/s. No or very low CMAP amplitudes peroneal (EDB) both sides and left tibial (AHB) nerve. Decreased or no SNAP amplitudes right median, left ulnar and right sural with decreased SNCVsh. No denervation, signs of reinnervation in predominantly distal leg muscles.Conclusion: severe axonal sensorimotor polyneuropathy.
H19-III-3, M (index)	7 years	62 years	Atrophy lower legs. Paralysis anterior tibialis muscles and toe extensors, paresis MRC 4 calf muscles. Flat feet. Distal sensory disturbances of the legs. Decreased vibration sense of the feet. Impaired joint position hallux. Absent Achilles tendon jerks.	Right median MNCV (APB) forearm 34 m/s; left ulnar MNCV (ADM) forearm 40 m/s. No recordable CMAPs peroneal both sides, EDB) and tibial (AHB) nerves. No recordable SNAPs right median (2nd finger), left ulnar (5th finger) and right sural nerve (lateral malleolus). Signs of reinnervation in the predominantly distal leg and arm muscles.Conclusion: severe sensorimotor polyneuropathy with axonal and demyelinating features.
H19-III-4, F	17 years	65 years	Paralysis feet, otherwise no examination performed.	Median MNCVs forearm left 11 m/s and right 17 m/s, although with very low CMAP amplitudes (APB) both sides; Ulnar MNCV forearm both sides 40 m/s, upper arm left 32 m/s and right 35 m/s with relatively normal CMAP amplitudes (ADM). Very low to non-recordable SNAP amplitudes in arms and legs. Signs of de- and reinnervation in predominantly distal arm muscles (legs not assessed). Conclusion: severe sensorimotor polyneuropathy with axonal and demyelinating features.
H19-IV-1, M	Early childhood	30 years	Atrophy and weakness MRC 4+ of distal leg muscles. Pes cavus and hammer toes. Slight sensory disturbances of the distal legs. Decreased Achilles tendon jerks.	Right median MNCV (APB) forearm 38 m/s; left ulnar MNCV (ADM) forearm 42 m/s. No CMAPs recordable left peroneal (EDB); decreased left CMAP amplitude of AHB muscle with decreased MNCV. No SNAPs recordable in arms and legs. No needle-EMG available. Conclusion: severe sensorimotor polyneuropathy with axonal and demyelinating features.
H19-IV-2, M	unknown	26 years	Weakness (MRC 4) of the distal arm and leg muscles. No foot deformities. No sensory disturbances. Absent Achilles tendon jerks. Extensor plantar response on the left.	Right median MNCV (APB) forearm 40 m/s; left ulnar MNCV (ADQ)i forearm 39 m/s. No CMAPs recordable from the peroneal (both sides) and left tibial nerve. Very low to non-recordable SNAPs in the arms and legs. Signs of reinnervation in distal and proximal arm and leg muscles. Conclusion: severe sensorimotor axonal polyneuropathy.
H19-IV-3, F	unknown	23 years	Data not available	Right median MNCV (APB) forearm 37 m/s; left ulnar MNCV (ADM) forearm 35 m/s; upper arm 50 m/s. No CMAPs peroneal (both sides) and left tibial nerve. Very low to non-recordable SNAPs in arms and legs. Signs of denervation in the distal leg muscles and signs of reinnervation in distal and proximal arm and leg muscles. Conclusion: severe sensorimotor polyneuropathy with axonal and demyelinating features.