Titinopathies: Phenotype – genotype heterogeneity in an Indian cohort
Bibliographic record
Abstract
Introduction: Titinopathies are heterogenous group of disorders affecting the skeletal and cardiac muscles variably and caused by Titin ( TTN) gene mutations located in Chromosome 2. The manifestations extend from congenital to adult-onset myopathies. Here we describe the phenotype-genotype heterogeneity of patients with myopathy/muscular dystrophy associated with TTN variants in an Indian cohort. Methods: A retrospective descriptive study of 12 patients diagnosed with primary muscle disease evaluated between 2016 and 2023 harboring rare TTN variants. Results: Eight patients were included (M:F ratio - 3:1). The median age at onset of entire cohort is 5 (range: birth- 33 years). The major clinical phenotypes were congenital myopathy [n = 3, 37.5%], juvenile onset myopathy [n = 3, 37.5%] and adult AD - Hereditary myopathy with early respiratory failure (HMERF) phenotype [n = 2, P6, P8; 25%]. Prominent / wide first interdigital space in feet in congenital and juvenile forms (c.38421_38437delinsC, c.106531 + 1G > A) was a novel feature. The variant c.95134T > C previously reported in HMERF in British population, was noted in two patients in our cohort and with GNE myopathy like phenotype in one. Muscle MRI done in congenital myopathy (c.26201-1G > A) showed fatty infiltration of anterior and posterior thigh with sparing of gracilis, adductor magnus and tibialis anterior. Conclusion: This is the first Indian study with a large cohort demonstrating many novel mutations and clinical heterogeneity expanding the spectrum of titinopathies.
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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".