Nemaline myopathy

As nemaline myopathy a rare muscle disease from the group of congenital myopathies is called, which was first described in 1963. Characteristic of the disease is the detection of filamentous (Greek nema νῆμα ) and rod-like structures in muscle biopsy.

Clinic

The spectrum is wide. Most frequently find progressive forms with hypotonia at birth (" floppy infant " ) and delayed motor development. However, most sufferers acquire the ability to walk independently; The course is usually slowly progressive.

Histology

Muscle biopsy can be seen in particular in the Gomori trichrome staining clusters of the characteristic rod- and fadenfärmigen structures. Interestingly, these changes were in 1958, the pathologist Ralph D. Douglas Kenneth Reye noticed in the muscle biopsy of a three- year-olds with delayed motor development. The changes had been but then incorrectly classified by a colleague to whom the case to a second opinion had been sent as an artifact.

Genetics

The disease is genetically heterogeneous extraordinary. have been described:

• Mutations of tropomyosin 3 gene, TPM3 ( nemaline myopathy -1; autosomal dominant inheritance )
• Mutations in the nebulin gene, NEM2 ( nemaline myopathy -2; autosomal recessive inheritance )
• Mutations of the alpha -actin gene, ACTA1 ( nemaline myopathy -3)
• Mutations of tropomyosin -2 gene, TPM2 ( nemaline myopathy 4)
• Mutations of Troponin T1 gene TNNT1 ( nemaline myopathy -5; Amish nemaline myopathy)
• Mutation of an unknown gene on chromosome 15q ( nemaline myopathy -6)
• Mutations of the Cofilin -2 gene, CFL2 ( nemaline myopathy -7)