TRPV4 相关骨骼发育不良。
TRPV4-associated skeletal dysplasias.
机构信息
Génétique Médicale, CHUV, Av. Decker 2, 1011 Lausanne, Switzerland.
出版信息
Am J Med Genet C Semin Med Genet. 2012 Aug 15;160C(3):190-204. doi: 10.1002/ajmg.c.31335. Epub 2012 Jul 12.
Dominant mutations in the TRPV4 gene result in a bone dysplasia family and form a continuous phenotypic spectrum that includes, in decreasing severity, lethal, and nonlethal metatropic dysplasia (MD), spondylometaphyseal dysplasia Kozlowski type (SMDK), and autosomal dominant brachyolmia. Several rare variant phenotypes that have some overlap but deviate in some ways from the general pattern have also been described. The known variant phenotypes are spondyloepiphyseal dysplasia Maroteaux type (Pseudo-Morquio type 2), parastremmatic dysplasia, and familial digital arthropathy with brachydactyly. Interestingly, different TRPV4 mutations have been associated with dominantly inherited neurologic disorders such as congenital spinal muscular atrophy and hereditary motor and sensory neuropathy. Finally, a small number of patients have been identified in whom a TRPV4 mutation results in a phenotype combining skeletal dysplasia with peripheral neuropathy. The TRPV4 gene encodes a regulated calcium channel implicated in multiple and diverse cellular processes. Over 50 different TRPV4 mutations have been reported, with two codons appearing to be mutational hot spots: P799 in exon 15, mostly associated with MD, and R594 in exon 11, associated with SMDK. While most pathogenic mutations tested so far result in activation of the calcium channel in vitro, the mechanisms through which TRPV4 activation results in skeletal dysplasia and/or peripheral neuropathy remain unclear and the genotype-phenotype correlations in this group of disorders remains somewhat mysterious. Since the phenotypic expression of most mutations seems to be relatively constant, careful clinical and radiographic assessment is useful in directing molecular analysis.
TRPV4 基因突变导致一种骨发育不良家族,并形成一个连续的表型谱,包括严重程度依次降低的致死性和非致死性变形性骨营养不良(MD)、脊椎干骺端发育不良 Kozlowski 型(SMDK)和常染色体显性短指(brachyolmia)。也已经描述了几种具有一些重叠但在某些方面偏离一般模式的罕见变异表型。已知的变异表型包括脊椎干骺端发育不良 Maroteaux 型(假性 Morquio 型 2)、副肋发育不良和伴有短指的家族性指关节病。有趣的是,不同的 TRPV4 突变与显性遗传神经疾病有关,如先天性脊髓性肌萎缩症和遗传性运动感觉神经病。最后,已经确定了少数患者,其中 TRPV4 突变导致骨骼发育不良与周围神经病变相结合的表型。TRPV4 基因编码一种调节钙通道,涉及多种不同的细胞过程。已经报道了超过 50 种不同的 TRPV4 突变,有两个密码子似乎是突变热点:外显子 15 中的 P799,主要与 MD 相关,以及外显子 11 中的 R594,与 SMDK 相关。虽然迄今为止测试的大多数致病性突变导致体外钙通道激活,但 TRPV4 激活导致骨骼发育不良和/或周围神经病的机制仍不清楚,并且该组疾病的基因型-表型相关性仍然有些神秘。由于大多数突变的表型表达似乎相对稳定,因此仔细的临床和影像学评估有助于指导分子分析。