Table 2.
Clinical features of the amyotrophic lateral sclerosis patients harbouring heterozygous, rare, non-synonymous MFN2 variants within the cohort under investigation
| # | Amino acid change | Family history | Sex | Age at onset (Ys) | Site of onset | Phenotype | Disease duration (Ys) | UMN signs | LMN signs | Bulbar/respiratory | Non-motor features |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | p.(His20Tyr) | sALS | M | 63 | UL | Flail arm | >1 | + | + | - | - |
| 2 | p.(Ser83Pro) | fALS | M | 68 | UL | Flail arm | 3 | + | + | + (NIV 17 months) | - |
| 3 | p.(Ala175Val) | sALS | F | 29 | UL | Classic | 12 | + | + | + (PEG 18 months) | - |
| 4 | p.(Asp194Ala) | fALS | F | 64 | LL | ALS-FTD | 3 | + | + | + | FTD |
| 5 | p.(Arg280His) | fALS | M | 58 | LL | PMA | 13 | - | + | + (NIV) | - |
| 6 | p.(Arg280His) | fALS | F | 69 | LL | PMA | 8 | - | + | - | - |
| 7 | p.(Thr362Met) | sALS | M | 56 | LL | Classic | >3a | + | + | - | Sensory symptoms (distal tingling paresthesias) Urinary symptoms (polyuria, incontinence) |
| 8 | p.(Val723Ala) | sALS | M | 65 | LL | Classic | >1a | + | + | + (NIV 10 months) | Sensory symptoms (distal tingling paresthesias) |
| 9 | p.(His750Tyr) | fALS | F | 51 | Bulbar | Bulbar | >1a | + | + | - | - |
ALS, amyotrophic lateral sclerosis; fALS, familial amyotrophic lateral sclerosis; sALS, sporadic amyotrophic lateral sclerosis; Ys, years; UMN, upper motor neuron; LMN, lower motor neuron; M, male; F, female; NIV, non-invasive ventilation; PEG, percutaneous endoscopic gastrostomy; FTD, frontotemporal dementia; PMA, progressive muscular atrophy; UL, upper limbs; LL, lower limbs.
aFollow-up not available.