Cure MFM13 - The Podcast

EP 7: Tedesco et al. 2025: How New Frameshifts Change HSPB8 Disease

17 min · 10 de sep de 2025
Portada del episodio EP 7: Tedesco et al. 2025: How New Frameshifts Change HSPB8 Disease

Descripción

In this episode, we look at the 2025 study by Tedesco et al., “Novel HSPB8 mutations in severe early-onset myopathy with involvement of respiratory and cardiac muscles cause proteostasis defects in cell models,” published in the European Journal of Human Genetics. The researchers revealed three new mutations in HSPB8 that result in a previously undescribed frameshift. These mutations create a longer C-terminal end of the protein with a different amino acid sequence than those described before. This structural change is linked to an even more severe disease picture: earlier muscle weakness, sometimes combined with reduced involvement, breathing difficulties, and even cardiac problems. The study not only presents detailed case reports but also builds on Tedesco et al., 2023 (Episode 5), which showed how elongated C-terminal mutations disrupt the cell’s clean-up system. In the 2025 work, scientists demonstrate that these new frameshifts also cause toxic aggregation of CASA complex proteins, further impairing the cell’s ability to remove damaged proteins. These results highlight the vulnerability of the HSPB8 gene’s last exon and broaden both the molecular and clinical understanding of HSPB8-related myopathies and neuromyopathies

Comentarios

0

Sé la primera persona en comentar

¡Regístrate ahora y únete a la comunidad de Cure MFM13 - The Podcast!

Prueba gratis

Empieza 7 días de prueba

$99 / mes después de la prueba. · Cancela cuando quieras.

  • Podcasts solo en Podimo
  • 20 horas de audiolibros al mes
  • Podcast gratuitos

Todos los episodios

12 episodios

episode EP 8: Clinical features of HSPB8 myopathy artwork

EP 8: Clinical features of HSPB8 myopathy

In this episode, we summarize what is known about Myofibrillar Myopathy type 13 (MFM13), previously referred to as HSPB8 Myopathy. Drawing on nine published case studies, we outline the main clinical features — progressive muscle weakness and atrophy, usually starting in the distal lower limbs and leading to foot drop and steppage gait. In some cases, weakness extends to proximal and axial muscles, occasionally affecting breathing or cardiac function. We also discuss the characteristic pathological findings seen in muscle biopsies: rimmed vacuoles, myofibrillar disorganization, and accumulation of proteins like HSPB8, BAG3, and TDP-43. MRI scans often reveal selective fatty degeneration of paraspinal and leg muscles. Finally, we highlight the key discovery that frameshift mutations in HSPB8 result in an abnormal C-terminal peptide extension, creating a toxic gain-of-function mechanism that disrupts autophagy and cellular proteostasis — defining the molecular basis of MFM13. Learn more about our work at curemfm13.org [http://curemfm13.org], and follow us on Facebook, LinkedIn, X, and Bluesky — just search for CureMFM13.

5 de ene de 202613 min