Considering that an alteration of calcium sensitivity has been recently reported in both NM patients with NEB or TPM mutations [22], [39] and in a mouse model carrying the Asp286Gly mutation in the ACTA1 gene [15], we indirectly assessed this parameter on the basis of in vivo measurements of force production resulting from incremental stimulation frequencies. This evidence concerns the gene ACTA1 and nemaline myopathy.