Sarcoglycanopathies : A clinico - pathological study

There have been few publications relating to limb girdle muscular dystrophy (LGMD) in India. In this issue Meena et al describe clinical and pathological features of 26 LGMD patients from South India. The LGMDs are an expanding group of diverse conditions, the term LGMD was first introduced in 1954 by Natrass and Walton to and there is reduced calpain on Western Blot analysis. LGMD2B is caused by mutations in the dysferlin gene. Onset is usually in late teenage years and may mimic acute myositis, the patient appearing normal prior to the onset. There is frequently weakness of the posterior peroneal compartment and, unusually for patients with pelvic girdle describe a category of patients that did not fit into the weakness, the patient cannot stand on his or her toes, the recognized disorders of Duchenne, Becker and CK is very high. LGMD2I is probably the most common Facioscapulohumeral muscular dystrophies. Limb LGMD in the UK, the phenotype is similar to Becker girdle muscular dystrophy is defined as a muscular muscular dystrophy, cardiomyopathy and respiratory dystrophy presenting with predominantly proximal involvement is frequent. Muscle biopsy shows a reduction weakness sparing facial, extraocular and distal muscles. in alpha dystroglycan and mutations are identified in the Onset can be in childhood or adulthood but not infancy. FKRP gene. A more severe congenital muscular Advances in molecular biology in recent years, have dystrophy with central involvement (MDC1C) is allelic resulted in the emergence of distinct genetic entities and with mutations also occurring in the FKRP gene. Alpha as a consequence a new numerical system of labeling dystroglycan is also reduced in muscle biopsies of patients was introduced by the European Neuromuscular Centre with LGMD2K, however, learning difficulty may be an Autosomal dominant LGMD is designated identifying feature of this entity. There is also a severe LGMD 1A, 1B, 1C etc and autosomal recessive LGMD congenital form, Walker Warburg syndrome, with allelic 2A, 2B, 2C etc; labeling is in the order of the mutations in the POMT1 gene. identification of the genetic loci. To date there are seven It is very encouraging to see a developing interest in dominant and 13 recessive forms, the latter being more the muscular dystrophy field in India. In due course this will lead to improved diagnostic accuracy and improved The sarcoglycanopathies (LGMD2 C, D, E and F) are a management of the patients suffering with these group of four genetically distinct but clinically similar conditions. muscular dystrophies. Each entity reflects the deficiency of a component of the complex of dystrophin-associated proteins. Onset is usually in childhood but can be later, Centre for Inherited Neuromuscular Disorders, Robert Jones the clinical picture is similar to Duchenne and Becker and Agnes Hunt NHS Trust, Oswestry, UK. muscular dystrophy and affected females can be mistaken for manifesting carriers of DMD. There is often tongue and calf hypertrophy, scapular winging, cardiac and respiratory involvement is common. In Europe, the References sarcoglycanopathies are relatively rare accounting for 5.6 cases per million in Italy and 25% of the ARLGMDs in 1. Meena AK, Sreenivas D, Sundaram C, Rajasekhar R, Sita JS, (ENMC).