摘要目的:对一个遗传性球形红细胞家系致病基因进行鉴定和突变致病性分析。方法:采集该家系共17人的外周血样。采用高通量测序分析先证者外周血DNA，筛选候选致病变异并进行家系共分离分析。然后采用同源重组构建pCAS2 c.5798＋1G和pCAS2 c.5798＋1A型质粒，转染293T细胞，应用反转录PCR、TA克隆和Sanger测序分析候选致病变异对剪接的影响，同时提取患者外周血RNA，分析候选致病变异在体内的剪接情况。 结果:高通量测序结果显示先证者携带 SPTB基因c.5798＋1G>A变异，且该变异与家系患者的表型共分离。体、内外剪接实验结果显示c.5798＋1G>A变异明显影响RNA的正常剪接，导致阅读框移码产生提前终止的密码子。 结论:SPTB基因c.5798＋1G>A新变异是导致该家系遗传性球形红细胞症的原因。

abstractsObjective:To explore the genetic basis of a pedigree affected with hereditary spherocytosis.Methods:Peripheral blood samples were collected from 17 members of the pedigree. Genomic DNA of the proband was subjected to next generation sequencing. Candidate variant was validated by co-segregation analysis. pCAS2 c.5798+ 1G and pCAS2 c.5798+ 1A plasmids were constructed by homologous recombination and transfected into 293T cells. Reverse transcription PCR, TA cloning and Sanger sequencing were used to analyze the effect of candidate variant on splicing. Meanwhile, peripheral blood RNAs were extracted to analyze the effect of candidate variant on splicing in vivo. Results:The proband was found to carry a c. 5798+ 1G>A variant of the SPTB gene. The variant has co-segregated with the phenotype in the pedigree. In vitro and in vivo splicing experiments confirmed that the mutation has significantly affected the splicing, resulting in shift of reading frame and produced a premature termination codon. Conclusion:The novel c. 5798+ 1G>A variant of the SPTB gene probably underlies the pathogenesis of hereditary spherocytosis in this pedigree.