Identification of a novel nemaline myopathy‐Causing mutation in the troponin T1 (TNNT1) gene: A case outside of the old order amish. Issue 5 (17th February 2015)

• Record Type: Journal Article
• Authors: Marra, Jonathan D.; Engelstad, Kristin E.; Ankala, Arunkanth; Tanji, Kurenai; Dastgir, Jahannaz; De Vivo, Darryl C.; Coffee, Bradford; Chiriboga, Claudia A.
• Is Part Of: Muscle & nerve. Volume 51:Issue 5(2015:May)
• Page Start: 767
• Page End: 772
• Publication Date: 2015-02-17
• Subjects: Amish nemaline myopathy (ANM) -- congenital myopathy -- nemaline myopathy -- TNNT1 -- slow skeletal muscle troponin T1; Neuromuscular diseases -- Periodicals; Muscles -- Periodicals; Nerves -- Periodicals; 616.74
• DOI: 10.1002/mus.24528
• Languages: English
• ISSNs: 0148-639X

Abstract

ABSTRACT: Introduction : Nemaline myopathy (NM) is a congenital neuromuscular disorder often characterized by hypotonia, facial weakness, skeletal muscle weakness, and the presence of rods on muscle biopsy. A rare form of nemaline myopathy known as Amish Nemaline Myopathy has only been seen in a genetically isolated cohort of Old Order Amish patients who may additionally present with tremors in the first 2–3 months of life. Methods : We describe an Hispanic male diagnosed with nemaline myopathy histopathologically and subsequently confirmed by next generation gene sequencing. Results : Direct sequencing revealed that he is homozygous for a pathogenic nonsense variant c.323C>G (p.S108X) in exon 9 of the TNNT1 gene. Conclusions : This report describes a novel pathogenic variant in the TNNT1 gene and represents a nemaline myopathy‐causing variant in the TNNT1 gene outside of the Old Order Amish and Dutch ancestry. Muscle Nerve 51 :767–772, 2015