β-原肌球蛋白缺失是与杆状体肌病相关的埃斯科瓦尔综合征的一个新病因。
Absence of beta-tropomyosin is a new cause of Escobar syndrome associated with nemaline myopathy.
作者信息
Monnier Nicole, Lunardi Joel, Marty Isabelle, Mezin Paulette, Labarre-Vila Annick, Dieterich Klaus, Jouk Pierre Simon
机构信息
Laboratoire de Biochimie et Génétique Moléculaire & Centre de Référence des Maladies Neuro-Musculaires, CHU Grenoble, France.
出版信息
Neuromuscul Disord. 2009 Feb;19(2):118-23. doi: 10.1016/j.nmd.2008.11.009. Epub 2009 Jan 19.
While TPM2 mutations identified so far in muscular diseases were all associated with a dominant inheritance pattern, we report the identification of a homozygous null allele mutation in the TPM2 gene in a patient who presented with a recessive form of nemaline myopathy associated with a non-lethal multiple pterygium syndrome (Escobar-MPS MIM# 265000). The TPM2 mutation led to a complete absence of the skeletal muscle isoform of beta-tropomyosin not compensated by expression of other beta-tropomyosin isoforms. Escobar syndrome has been recently described as a prenatal form of myasthenia associated with recessive mutations in genes of the neuromuscular junction (CHRNG, CHRNA1, CHRND, RAPSN). This observation expands the cause of Escobar variant-MPS to a component of the contractile apparatus. This first report of the clinical expression of the complete absence of TPM2 in human indicated that TPM2 expression at the early period of prenatal life plays a major role for normal fetal movements.
虽然迄今为止在肌肉疾病中鉴定出的TPM2突变均与显性遗传模式相关,但我们报告了一名患有隐性杆状体肌病并伴有非致死性多发性翼状胬肉综合征(Escobar-MPS,MIM# 265000)的患者中TPM2基因纯合无效等位基因突变的鉴定。TPM2突变导致骨骼肌β-原肌球蛋白亚型完全缺失,且未被其他β-原肌球蛋白亚型的表达所补偿。Escobar综合征最近被描述为一种与神经肌肉接头基因(CHRNG、CHRNA1、CHRND、RAPSN)隐性突变相关的先天性重症肌无力形式。这一观察结果将Escobar变异型-MPS的病因扩展到了收缩装置的一个组成部分。人类中TPM2完全缺失的临床表型的首次报道表明,产前早期TPM2的表达对正常胎儿运动起着重要作用。