TABLE 2.
Clinical radiologic and molecular characteristics of 12 patients diagnosed with channelopathies
| Identification | 521 | 620 | 800 | 895_MT0181 | 895_MT0182 | 671 | 6712 | 6713 | 254b | 423 | 552 | 614 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gene | CACNA1A | CACNA1A | CACNA1A | CACNA1A | CACNA1A | CACNA1G | CACNA1G | CACNA1G | ITPR1 | ITPR1 | ITPR1 | KCNC1 |
| Pathogenic variant | c.593G>A (p. Arg198Gln) | c.1999G>A (p. Glu667Lys) | c.4055G>A (p. Arg1352Gln) | Deletion of exons 23 to 47 | Deletion of exons 23 to 47 | c.5144G>A (p. Arg1715His) | c.5144G>A (p. Arg1715His) | c.5144G>A (p. Arg1715His) | c.7748 T>C (p. Ile2583Thr) | c.800C>T (p. Thr267Met) | c.7727A>C (p. Asn2576Thr) | c.959G>A (p. Arg320His) |
| De novo | N/A | + | + | − | − | − | − | − | + | + | + | + |
| Sex/age, yr | F/61 | M/20 | F/8 | M/29 | F/32 | F/65 | M/33 | F/53 | F/11 | F/10 | M/14 | F/17 |
| Age at onset of ataxia, yr | 35 | 1 | 1 | Teens | Teens | 30 | 28 | 20s | 1.5 | 1 | 2 | 4 |
| Presenting symptoms | Ataxia | GDD,Hypotonia | GDD,Hypotonia | Ataxia | Ataxia | Ataxia | Ataxia | Ataxia | Hypotonia | GDD | Hypotonia | Ataxia |
| Gait ataxia/limb ataxia | +/‐ | +/+ | +/+ | +/+ | +/+ | +/+ | +/‐ | +/+ | +/+ | +/+ | +/+ | +/+ |
| Progressive ataxia | + | − | − | + | + | + | + | + | + | − | + | − |
| Walking aid required | + | − | + | + | − | − | − | − | + | + | + | − |
| Developmental delay | − | + | + | − | − | − | − | − | + | + | + | − |
| Cognitive impairment | − | + | + | + | − | − | − | + | + | + | + | + |
| Nystagmus | + | + | + | + | + | − | − | + | + | − | + | + |
| Dysarthria | + | + | + | + | − | + | + | + | + | + | + | + |
| Bulbar symptoms | + | − | − | − | − | + | − | − | − | − | − | − |
| Episodic symptoms | − | − | − | + | + | − | − | − | + | − | − | − |
| Headache | + | + | − | − | + | − | − | − | − | − | − | + |
| Muscle weakness | + | − | + | − | − | − | − | + | + | − | + | − |
| Upper motor neuron signs | − | − | + | − | − | − | − | − | − | − | − | − |
| Seizures | − |
+ FS |
− | − | − | − | − | + GTC | − | − | − | + M, GTC |
| Isolated cerebellar atrophy on neuroimaging | + | + | + | + | − | + | N/A | + | + | + | + | + |
N/A, not available; F, female; M, male; GDD, global developmental delay; FS, febrile seizures; GTC, generalized tonic–clonic seizures; M, myoclonic seizures.