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10 | InTouch JUNE 2022 Limb Girdle Muscular Dystrophy (LGMD) is an umbrella name for a group of inherited disorders. Limb Girdle Muscular Dystrophy (LGMD affects the proximal muscles (those closest to the centre of the body) of the hip and shoulder areas – the pelvic and shoulder girdles, also known as the limb girdles. These muscles weaken and waste away (atrophy), and as a progressive disorder, it may involve other muscles over an individual’s lifetime. Symptoms include difficulties running, walking with a ‘waddling’ gait, having trouble getting out of chairs, rising from a toilet seat, or climbing stairs. As this weakness progresses, the person may require the use of assistive mobility devices. Weakness usually occurs first in the legs but then progresses to the arms and shoulder area which can make reaching over the head, holding the arms outstretched, or carrying heavy objects difficult. Diagnosis has improved markedly in recent years and is usually completed through DNA analysis and a muscle biopsy if needed. It is recommended that genetic counselling is arranged so that inheritance issues and any risks to other family members can be discussed https://www. genetichealthservice.org.nz/ The onset of one of the LGMD conditions can occur in childhood, or symptoms may not be apparent until adolescence or adulthood. Males and females are equally Limb Girdle Muscular Dystrophy (LGMD) YOUR CONDITION IN REVIEW affected, however it is difficult to give generalised information on how the condition will progress because different LGMDs progress at different rates, even within the same family. In addition, each different type has some specific features and characteristics, such as age of onset of symptoms and particular muscles involved. The brain, intellect and senses are unaffected. Causes of Limb Girdle Muscular Dystrophy The various forms of LGMD are caused by mutations in many different genes. These genes provide instructions for making proteins that are involved in muscle maintenance and repair. When these proteins are not produced properly due to a faulty gene or genes, the cells in the muscles fail to function as they should. Types of Limb Girdle Muscular Dystrophy Most types of LGMD are inherited in an autosomal recessive manner and some in an autosomal dominant manner. The old classification of these conditions was 1 for a dominant inheritance and 2 for a recessive inheritance followed by a letter showing order of discovery. However, with more genes being discovered and the alphabet all used up there needed to be a change in classification – which occurred in 2017. Consequently the term LGMD is now followed by the letter D when the disease is inherited in an autosomal dominant manner and by an R if it is inherited in a recessive manner. Subsequently, the disease is given a number in the order in which the disease is discovered over time and finally, the name of the protein that is not (or incorrectly) produced. For example LGMD 2A is now known as LGMD R1 Calpain 3 related. This diagram shows which muscles experience weakness with LGMD.