一个新的MPL基因异常剪接体MPL L391-V392ins12的鉴定及其在248例骨髓增殖性肿瘤患者中的筛查结果

Identification of a novel aberrant spliceosome of MPL gene （MPLL391-V392ins12） in patients with myeloproliferative neoplasms

目的 鉴定MPL L391-V392ins12异常剪接体,了解其在骨髓增殖性肿瘤（MPN）患者中突变发生情况.方法 采用逆转录聚合酶链反应（RT-PCR）联合克隆测序方法对MPL基因异常剪接体进行鉴定,采用等位基因特异性聚合酶链反应（AS-PCR）在248例MPN患者及200名健康正常人中筛查其突变情况.结果 发现并确认了MPL基因的一个异常剪接体MPL L391-V392ins 12,即MPL基因的外显子7和外显子8之间保留了36 bp的内含子序列,导致蛋白编码序列的氨基酸位点391与392之间插入12个氨基酸（谷氨酸、甘氨酸、亮氨酸、赖氨酸、亮氨酸、亮氨酸、脯氨酸、丙氨酸、天冬氨酸、异亮氨酸、脯氨酸、缬氨酸）.248例MPN患者中19例（7.66％）检出MPL L391-V392ins12突变,真性红细胞增多症（PV）、原发性血小板增多症（ET）、原发性骨髓纤维化（PMF）患者的检出率分别为1.92％（1/52）、9.66％（14/145）、7.84％ （4/51）;200名正常人中未检测到MPL L391-V392ins12突变.结论 MPL L391-V392ins12是存在于MPN中的一种病理性剪接体,在PV、ET、PMF中均可发生,但多见于ET、PMF,可能是MPN发病的潜在原因之一.

Objective To identify the MPL L391-V392ins12 spliceosome and analyze its frequencies in patients with myeloproliferative neoplasms （MPN）.Methods MPL aberrant spliceosome was identified through reverse transcription polymerase chain reaction （RT-PCR） combined with cloning sequencing.The mutation of this spliceosome in 248 MPN patients and 200 normal people was determined by allele-specific polymerase chain reaction （AS-PCR）.Results A novel aberrant spliceosome of MPL gene （MPL L391-V392ins12） was identified,i.e.36 bp intron was retained between exon7 and exon8,and there were 12 amino acids （EGLKLLPADIPV） inserted.MPL L391-V392ins 12 mutation was detected in 19 （7.66%） of the 248 patients with MPN,including 1 （1.92%） of 52 patients with PV,14 （9.66%） of 145 with ET,and 4 （7.84%） of 51 with PMF.And the mutation was not detected in the group of 200 normal people.Conclusion MPL L391-V392ins12 spliceosome is an aberrant spliceosome present in the MPN.It can be detected in PV,ET and PMF,and more frequently in ET and PMF.This mutation may play an important role in the process of MPN.