Limb Girdle Muscular Dystrophies (LGMD)

Limb girdle muscular dystrophies (LGMD) is a general term used to describe a diverse cluster of neuromuscular disorders and they are usually being inherited. They are caused by mutations of certain genes which results in respective defective proteins being generated. These defective proteins are usually involved in the direct or indirect stabilizing of the membrane of the muscle. This disorder involves symptoms like primary or secondary weakening of limb and axial muscles, muscle wasting and joint contractures (a loss of a variety of motion in a joint due to numerous alterations in connective tissue and muscle during immobilizing period) Though they are inherited, most of them becomes apparent during adulthood. There are two general types of LGMD namely, LGMD1 and LGMD2. LGMD1 is being caused when 1 abnormal gene copy is present whereas LGMD2 is caused when 2 abnormal gene copies are present. There are many types of LGMD and one of them is LGMD 2B.

Figure 1 shows the distribution of main muscle weakening found in various types of dystrophy conditions through the shaded areas. C-limb-girdle dystrophy.

LGMD2B is resulted where there is a mutation in dysferlin gene encoding protein. In this disorder, tissues are being …show more content…
Repair of membrane is carried out by exocytosis of different intracellular vesicles provoked by rapid calcium. This results in membrane patch being formed to reseal damaged area of the membrane. Findings indicated that dysferlin play a vital role in muscle repairing process. They possibly play a part as a calcium sensor that provokes fusing of vesicle. These findings of functions are not proven however it is based on findings regarding the structure of dysferlin. It has six C2 domains and the C2 domains are sensitive to calcium. Other 2 proteins like C elegans and otoferlin has similar structure of C2 domain and they play a part