A new autosomal recessive spastic ataxia associated with frequent white matter changes maps to 2q33-34
Bibliographic record
Abstract
Recessive ataxias are a heterogeneous group of diseases. We identified a group of 23 French-Canadian cases belonging to 17 families affected by an autosomal recessive spastic ataxia associated with frequent white matter changes. The fact that 59% of these families have a genealogical relationship to the Portneuf County of Quebec suggests that this is a new form of ataxia with a regional founder effect. All cases present with cerebellar ataxia and spasticity. There is great intrafamilial and interfamilial variability, as illustrated by the spectrum of age of diagnosis (range: 2-59 years, mean: 15.0) and the presence of white matter changes on MRI in 52.4% of cases. The more severe cases have spasticity from birth, scoliosis, dystonia and cognitive impairment and were considered cases of cerebral palsy. Brain MRI constantly shows cerebellar atrophy, which in some cases may be associated with cortical atrophy, leucoencephalopathy and corpus callosum thinning. A genome wide scan uncovered linkage of three families to marker D2S2321 localized on chromosome 2q33-34. Linkage analysis confirmed that all families are linked to the same region [multipoint log of the odds (LOD) score of 5.95]. Haplotype analysis and allele sharing suggest that one common mutation may account for 97% of carrier chromosomes in Quebec. The uncovering of the mutated gene may point to a common pathway for pyramidal and cerebellar degeneration as both are often observed in recessive ataxias and complicated paraplegias.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".