Primary Evidence Review
Distinguishing a defined splice variant, familial findings and experimental loss of lamin A/C
Related long-form Word draft: its topic title was checked, but its scientific claims and bibliography were not revalidated in this batch. The concise HTML below has its own checked primary-evidence scope.
Source file: Lamin A Mutants Aging Review_.docx | Match confidence: medium
A defined point/splice variant, a family co-segregation result and complete loss of lamin A/C are different forms of evidence. This concise page compares selected LMNA findings without assuming they are interchangeable or establish a complete aging mechanism. Eriksson et al. (2003); Bonne et al. (1999); Lammerding et al. (2004).
This HTML is a concise review of the selected primary evidence linked below. The related Word draft has a broader scope and has not been scientifically revalidated in this batch.
Bonne et al. identified four LMNA variants co-segregating with autosomal-dominant Emery-Dreifuss muscular dystrophy in five families. Eriksson et al. identified recurrent G608G in 18 of 20 classical HGPS cases and a cryptic splice-site consequence. These results are explicit in the primary abstracts; detailed family/case methods were not appraised. Bonne et al. (1999); Eriksson et al. (2003).
A lamin filament meshwork was resolved by cryo-electron tomography in extracted, chromatin-reduced mouse fibroblast nuclei. That structural result supplies a specific normal-architecture context; it does not establish the effect of every possible lamin variant. Turgay et al. (2017).
The recurrent G608G change in the Eriksson study activates a cryptic splice site and produces a protein product lacking 50 amino acids. The primary abstract also describes abnormal nuclear membranes in patient fibroblasts. This is a bounded genotype/splice/morphology finding, not evidence that every tail-domain alteration has the same clinical or mechanical effect. Eriksson et al. (2003).
The four variants reported by Bonne et al. include one nonsense and three missense changes. Their family association does not by itself identify one assembly defect or prove a domain-based classification that predicts every patient phenotype. Bonne et al. (1999).
Lammerding et al. compared lamin-A/C-null and wild-type mouse embryo fibroblasts. Null nuclei deformed more under applied cell strain, and cells showed reduced viability under strain and altered selected transcriptional responses. Complete absence of lamin A/C in this model is not equivalent to an unspecified deletion construct or every human point variant. Lammerding et al. (2004).
Stephens et al. examined chromatin and lamin-A/C contributions to force-extension responses of isolated nuclei. The measured contributions depend on that preparation and deformation range; they are not a direct aging assay or a test of every LMNA allele. Stephens et al. (2017).
Freund et al. found lower lamin-B1 in several primary human fibroblast senescence conditions, while quiescent controls retained it. That concerns a different lamin, defined cell states and an irradiated-mouse tissue comparison; it does not establish that all lamin-A variants accelerate ordinary human aging. Freund et al. (2012).
The HGPS case findings and the lamin-A/C-null mechanical model remain distinct. Neither establishes a complete normal-aging mechanism, universal variant penetrance or clinical intervention effectiveness. The selected review does not claim an exhaustive mutant panel. Eriksson et al. (2003); Lammerding et al. (2004).
Petrini and colleagues examined skin fibroblasts from two laminopathic patients. Confocal/STED co-distribution and antibody-based lifetime/FRET measurements supported closer association of Src and lamin A/C in the tested patient samples. The small, defined comparison does not establish a universal mutation effect, a mechanical modulus or a causal mechanism of ordinary ageing. Petrini et al. (2024).
Reassessed 12 October 2026. Recent-source access is stated above; complete supplementary material and raw data were not reanalysed. The archived Word draft remains a separate, unreconciled document.