In normal muscle cells, the various parts of the muscle fibers that make up the sarcomere are distributed evenly in a pattern for effective muscle contraction. Evidence suggests that some kinds of NM affect the arrangement of these muscle fibers, causing the muscles to be unable to contract as efficiently or effectively. Nemaline myopathy is usually genetic and shows traits in the affected individual from birth or an early age. However, there are some cases of symptoms of nemaline myopathy not showing up until adulthood. These cases are usually not genetic. Of the genes that have been linked to nemaline myopathy, most are also involved in encoding proteins in the sarcomeres in the muscle cells. Respiratory muscles are often more affected than other skeletal muscle groups. Cardiac muscle is usually not affected in nemaline myopathy; however, in cases where it does, patients often present with dilated cardiomyopathy. The ocular muscles are usually spared.The different genes whose mutations lead to the different kinds of nemaline myopathies affect the cells and the persons body differently. The first kind of nemaline myopathy identified is due to the Slow α-Tropomyosin Gene TPM3 and varies from case to case with its severity. In this kind of nemaline myopathy, affected people are weaker and more affected in their lower limbs than their upper limbs.As stated above, the most common genetic form of NM is caused by a mutation in the nebulin gene, called Nebulin, and has a range of severity levels.
Many more conferences and social events have been held since, and all events organized since 2008 have been co-sponsored by A Foundation Building Strength for Nemaline Myopathy (AFBS), the only foundation focused on supporting treatment development and social events for the NM community. In March 2006, Niki Shisler released a book, Fragile, in which she recounted her experiences surrounding the birth of twin sons with severe NM. In 2014, a team of experts collaborated with affected individuals and families caring for someone with a congenital myopathy to develop the first guidebook on managing life with a congenital myopathy

References
External links
GeneReview/NCBI/NIH/UW entry on Nemaline Myo\