Table 1.
Phenotypes of Cacna1a alleles
| tottering | leaner | rolling | tottering-3J | rocker | tg/la | tg/rol | rkr/la | |
|---|---|---|---|---|---|---|---|---|
| Viability | Normal | Reduced | Normal | Reduced | Normal | Normal | Normal | Normal |
| Age of onset of ataxia | P21–28 | P8–10 | P10–14 | P12–14 | P21–28 | P15–17 | P10–14 | P15–17 |
| Ataxia | + (1) | +++ (1) | ++ (2) | +++ (3) | + | ++ (1) | ++ (2) | ++ |
| Paroxysmal dyskinesia | + (4–6) | – | – | ? | – | + (1) | – | ? |
| Absence seizures | + (4–6) | + (7) | – ? (8) | + ? (3) | + | + (7) | ? | + ? |
| Increased LC innervation | + (9) | ? | + (10) | ? | ? | ? | ? | – ? |
| Cerebellar cell death | – (11, 12) | + (9) | + (11, 13)/– (14, 15) | ? | – | – (12) | ? | – ? |
| Purkinje cell TH expression | + (16, 17) | + (16, 17) | + (18) | ? | – | + (17) | ? | + |
| Purkinje cell axonal torpedoes | + (19) | + (19) | + (20) | ? | – | + (19) | ? | – |
| Purkinje cell ectopic spines | + (19) | + (19) | + (20) | ? | – | + (19) | ? | + |
| Purkinje cell dendritic weeping | – | – | ? | ? | + | ? | ? | – |
| Purkinje cell current density | 60% of control (21) | 40% of control (21, 22) | 60% of control (15) | ? | ? | ? | ? | ? |
+++, Strong phenotype; ++, moderate phenotype; +, mild phenotype; –, no overt phenotype; ?, needs further study.
1, Meier and MacPike (1971); 2, Oda (1973); 3, Green et al. (1988); 4,Green and Sidman (1962); 5, Sidman et al. (1965); 6, Noebels and Sidman (1979); 7, Noebels (1984); 8, Oda (1981); 9, Levitt and Noebels (1981); 10, Muramoto et al. (1982); 11, Nakane (1976); 12, Isaacs and Abbott (1995); 13, Nishimura (1975); 14, Mukaiyama and Mizuno (1976); 15, Mori et al. (2000); 16, Hess and Wilson (1991); 17, Austin et al. (1992); 18, Muramoto et al. (1981); 19, Rhyu et al. (1999a); 20, Rhyu et al. (1999b); 21, Wakamori et al. (1998); 22, Dove et al. (1998).