Table 1.
Classification of distal hereditary motor neuronopathy
| HMN subtype (alias) | Locus | Gene | Inheritance | Clinical hallmarks |
|---|---|---|---|---|
| I | Unknown | Unknown | AD | Juvenile onset |
| II (CMT2L) | 12q24.3 | HSP22 | AD | (Early)-adult onset |
| (CMT2F) | 11q11-q21 | HSP27 | AD | (Early)-adult onset |
| III | 11q13 | Unknown | AR | Early-adult onset, slowly progressive |
| IV | 11q13 | Unknown | AR | Juvenile onset, severe course, paralysis diaphragm |
| V (CMT2D) | 7p15 | GARS | AD | Upper limb predominance, pyramidal features may occur |
| (Silver syndrome) | 11q12–q14 | BSCL2 | AD | Prominent atrophy of hands, spasticity of lower limbs |
| VI (SMARD1) | 11q13.2–13.4 | IGHMBP2 | AR | Infantile onset, severe course, involvement diaphragm (SMA-RD: respiratory distress) |
| VII | 2q14 | Unknown | AD | Adult onset, vocal cord paralysis |
| VII | 2p13 | DCTN1 | AD | Adult onset, vocal cord paralysis, facial weakness |
| n.a. (ALS4) | 9q34 | SETX | AD | Early onset, pyramidal features |
| n.a. (HMN-Jerash) | 9p21.1-p12 | Unknown | AR | Juvenile onset, pyramidal features |
| n.a. (congenital SMA) | 12q23-q24 | Unknown | AD | Congenital, non-progressive, contractures |
| n.a | 1p36 | PLEKHG5 | AR | Childhood onset, severe course |
| DSMAX. | Xq13.1-q21 | Unknown | X-linked | Juvenile onset |
HMN hereditary motor neuronopathy, CMT Charcot–Marie–Tooth, ALS amyotrophic lateral sclerosis, SMA spinal muscular atrophy, AD autosomal dominant, AR autosomal recessive, n.a. not applicable