日本研究人员最近确认了一种遗传性重听基因。动物试验表明，激活这种名为C－RET的基因有助于恢复患者的听力。

日本中部大学教授加藤昌志和讲师大神信孝领导的研究小组发现，C－RET基因具有促进神经生长和维持神经功能的作用。在老鼠身上进行的试验表明，如果关闭C－RET基因，老鼠内耳中负责传递声音信息的神经细胞数目将大量减少，最终导致重听症状；而激活C－RET基因，相关神经细胞数目又恢复到原有水平，听力也随之恢复。

研究小组随即对遗传性重听患者进行调查，结果也确认这些患者的C－RET基因功能异常。

这项研究成果29日发表在美国《国家科学院学报》网络版上。

上月底，日本京都大学与美国国立卫生研究院研究人员曾在美国《细胞》杂志上报告说，如果一种名为TRIOBP的基因出现变异，患者也会患上重听(详细内容-Cell：发现听觉迟钝的新致病基因TRIOBP)。

遗传性重听的发病率约为千分之一。虽然基因异常被认为是导致重听的原因，但其致病机制一直没有弄清。

原文出处：

PNAS doi: 10.1073/pnas.1004520107

c-Ret–mediated hearing loss in mice with Hirschsprung disease
Nobutaka Ohgamia, Michiru Ida-Etoa, Takashi Shimotakeb, Naomi Sakashitac, Michihiko Soned, Tsutomu Nakashimad, Keiji Tabuchie, Tomofumi Hoshinoe, Atsuyoshi Shimadaf, Toyonori Tsuzukig, Masahiko Yamamotoh, Gen Sobuei, Mayumi Jijiwaj, Naoya Asaij, Akira Harae, Masahide Takahashij, and Masashi Katoa,1

A significantly increased risk for dominant sensorineural deafness in patients who have Hirschsprung disease (HSCR) caused by endothelin receptor type B and SOX10 has been reported. Despite the fact that c-RET is the most frequent causal gene of HSCR, it has not been determined whether impairments of c-Ret and c-RET cause congenital deafness in mice and humans. Here, we show that impaired phosphorylation of c-Ret at tyrosine 1062 causes HSCR-linked syndromic congenital deafness in c-Ret knockin (KI) mice. The deafness involves neurodegeneration of spiral ganglion neurons (SGNs) with not only impaired phosphorylation of Akt and NF-κB but decreased expression of calbindin D28k in inner ears. The congenital deafness involving neurodegeneration of SGNs in c-Ret KI mice was rescued by introducing constitutively activated RET. Taken together with our results for three patients with congenital deafness with c-RET–mediated severe HSCR, our results indicate that c-Ret and c-RET are a deafness-related molecule in mice and humans.