RT Journal Article
SR Electronic
T1 The effect of calpain 3 deficiency on the pattern of muscle degeneration in the earliest stages of LGMD2A
JF Journal of Clinical Pathology
JO J Clin Pathol
FD BMJ Publishing Group Ltd and Association of Clinical Pathologists
SP 624
OP 626
DO 10.1136/jcp.56.8.624
VO 56
IS 8
A1 M Vainzof
A1 F de Paula
A1 A M Tsanaclis
A1 M Zatz
YR 2003
UL http://jcp.bmj.com/content/56/8/624.abstract
AB Limb girdle muscular dystrophy type 2A (LGMD2A) is caused by mutations in the calpain 3 gene. In a large family affected by LGMD2A with four severely affected members, three additional asymptomatic relatives had very high serum creatine kinase concentrations. All were homozygous for the R110X mutation and showed a total absence of calpain 3 in the muscle. Histological analysis of muscle in these three rare preclinical cases showed a consistent but unusual pattern, with isolated fascicles of degenerating fibres in an almost normal muscle. This pattern was also seen in one patient with early stage LGMD2A who had a P82L missense mutation and a partial deficiency of calpain 3 in the muscle, but was not seen in early stage patients affected by other forms of LGMD. These findings suggest that a peculiar pattern of focal degeneration occurs in calpainopathy, independently of the type of mutation or the amount of calpain 3 in the muscle.