In the Italo-Spanish family, the mutation was identified in a single nucleotide deletion (c.2771delA, p.X924C, exon22) in the TNPO3 gene while in the Hungarian family the causative mutation of LGMD D2 is due to an heterozygous frameshift deletion c.2767delC. in exon 23.

A group of miRNAs are highly expressed in skeletal and cardiac muscle and they are called myomiRs. The myomiR family includes miR-1, miR-133a, miR-133b, miR-206 which are used as non-invasive biomarkers in neuromuscular diseases.

We obtained clinical data, including onset and progression of the disease, from the four patients in two different trasportinopathy  Italo-Spanish and Hungarian families. The onset of symptoms was often characterized by difficulty in walking or climbing stairs, collected by a standard LGMD questionnaire. Muscle MRI was done 1.5 Tesla Philips apparatus.

Circulating myomiRs (miR-1, miR-206, miR-133a/b) were analysed in serum.

MiR-206 was over 80 fold elevated in a child compared to controls, that started presenting a severe evolutive congenital myopathy Limb Girdle clinical pattern and recently lost walking ability is possible only with support. In the mother miR-206 was about 4 fold. In the patients from Italian-Spanish family the expression level of miR-206 was up-regulated between 4 to 10 fold. MiR-1 was also eleveted in Hungarian family.

Muscle MRI of daughter and mother of Italo-spanish family showed pronounced atrophy in posterior thigh muscles. In son and mother of Hungarian family we observed generalized muscle atrophy. 

This study provids the first evidence that miR-206 correlate with phenotypic expression and is a prognostic indicator of LGMDD2 disease progression.