CAJ | 학술논문

目的：对遗传性多发性骨软骨瘤致病基因EXT1一个新的剪接突变进行分析，并研究其致病机制。方法2013年4月厦门大学附属福州第二医院骨肿瘤科收治的多发性骨软骨瘤患者即先证者因全身多处关节畸形20余年于门诊收入院，采集先证者及父母外周血并提取基因组DNA， PCR扩增EXT1／EXT2基因编码区及邻近内含子序列并测序；生物信息学分析所得突变；以先证者、母亲及正常人血组织cDNA为模板，扩增EXT1基因编码区并将产物做TA克隆测序，用卡方检验统计分析各组异常转录本数以研究该突变的致病机制。结果基因测序发现先证者及母亲EXT1基因第4内含子5′剪接位点存在杂合性缺失突变（c．1284＋2del）；生物信息学预测该突变可导致外显子4跳跃或异常剪接；TA克隆测序及统计分析表明先证者及母亲含外显子4跳跃的转录本其比例均明显高于正常人（P＝0．000，P＜0．01）。结论 EXT1基因突变c．1284＋2del导致较大数量的EXT1基因转录本外显子4跳跃，而影响其正常转录翻译。（中华检验医学杂志，2015，38：672－676）
목적：대유전성다발성골연골류치병기인EXT1일개신적전접돌변진행분석，병연구기치병궤제。방법2013년4월하문대학부속복주제이의원골종류과수치적다발성골연골류환자즉선증자인전신다처관절기형20여년우문진수입원，채집선증자급부모외주혈병제취기인조DNA， PCR확증EXT1／EXT2기인편마구급린근내함자서렬병측서；생물신식학분석소득돌변；이선증자、모친급정상인혈조직cDNA위모판，확증EXT1기인편마구병장산물주TA극륭측서，용잡방검험통계분석각조이상전록본수이연구해돌변적치병궤제。결과기인측서발현선증자급모친EXT1기인제4내함자5′전접위점존재잡합성결실돌변（c．1284＋2del）；생물신식학예측해돌변가도치외현자4도약혹이상전접；TA극륭측서급통계분석표명선증자급모친함외현자4도약적전록본기비례균명현고우정상인（P＝0．000，P＜0．01）。결론 EXT1기인돌변c．1284＋2del도치교대수량적EXT1기인전록본외현자4도약，이영향기정상전록번역。（중화검험의학잡지，2015，38：672－676）
Objective To analyse a novel splice mutation in EXT1 gene of hereditary multiple osteochondroma, and study its pathogenic mechanism.Methods In April of 2013, the proband was hospitalized from the outpatient department with multiple joint deformity for more than 20 years, peripheral blood of the proband and his parents were collected and genomic DNA was extracted .Coding regions and adjacent intron sequences of EXT1/EXT2 genes in genomic DNA of the family members were amplified and sequenced.Bioinformatics was used to analyze the mutation from sequencing .cDNA from peripheral blood of the proband ,the mother and normal control was made respectively as a template for amplifying coding regions of EXT1 gene, and the product was T-A cloned and sequenced.The abnormal transcripts of each group were counted and analyzed using chi square test to study the pathogenic mechanism of the mutation .Results Sequencing results of family members revealed that there was a heterozygous deletion mutation ( c.1284 +2del) in the 5′splice site of intron 4 in EXT1 gene of the proband and his mother .Bioinformatics predicted that exon 4 of EXT1 gene was skipping or spliced aberrantly due to the mutation .T-A clone and sequencing results as well as the statistical analysis suggested that there was a significantly higher proportion of transcripts with skipping exon 4 in the proband and his mother compared with the normal control (P=0.000, P<0.01).Conclusions c.1284+2del in EXT1 gene is reported for the first time internationally , which results in a considerable number of abnormal transcripts with skipping exon 4 in EXT1 gene, thereby influences the normal transcription and translation of EXT1 gene.