背景:遗传性溶血性贫血(HHA)被定义为一组由红细胞(RBC)代谢和红细胞膜缺陷引起的异质性和罕见疾病,导致裂解或过早清除。这项研究的目的是调查患有HHA的个体在被报道与HHA相关的33个基因中潜在的致病变异。
方法:共有14个独立的个体或家庭被诊断为疑似HHA,特别是,红细胞膜病,红细胞酶病,和血红蛋白病,在常规外周血涂片检测后收集。一个定制设计的面板,包括33个基因,在IonTorrentPGM™Dx系统上使用基因面板测序进行。通过Sanger测序确认了最佳候选致病变异。
结果:在14名疑似HHA个体中有10名检测到HHA相关基因的几种变异。排除那些预测为良性的变异后,在10名疑似HHA的个体中证实了10种致病性变异和1种不确定意义的变异(VUS)。在这些变体中,EPB41的p.Trp704Ter无义变体和SPTA1的错义p.Gly151Asp变体在四个遗传性椭圆细胞症中的两个中被鉴定。ANK1的移码p.Leu884GlyfsTer27变体,SPTB的无义p.Trp652Ter变体,在所有4例遗传性球形红细胞增多症病例中均检测到PKLR的p.Arg490Trp变体。错觉p.Glu27Lys,胡说八道p.Lys18Ter变体,在4例β地中海贫血病例中发现了剪接错误,如HBB中c.92+1G>T和c.315+1G>A。
结论:本研究提供了一组韩国HHA个体的遗传改变的快照,并证明了在HHA中使用基因面板的临床实用性。遗传结果可以为某些个体的医疗和管理提供精确的临床诊断和指导。
BACKGROUND: Hereditary hemolytic anemia (HHA) is defined as a group of heterogeneous and rare diseases caused by defects of red blood cell (RBC) metabolism and RBC membrane, which leads to lysis or premature clearance. The aim of this study was to investigate individuals with HHA for potential disease-causing variants in 33 genes reported to be associated with HHA.
METHODS: A total of 14 independent individuals or families diagnosed with suspected HHA, and in particular, RBC membranopathy, RBC enzymopathy, and hemoglobinopathy, were collected after routine peripheral blood smear testing. A custom designed panel, including the 33 genes, was performed using gene panel sequencing on the Ion Torrent PGM™ Dx System. The best candidate disease-causing variants were confirmed by Sanger sequencing.
RESULTS: Several variants of the HHA-associated genes were detected in 10 out of 14 suspected HHA individuals. After excluding those variants predicted to be benign, 10 pathogenic variants and 1 variant of uncertain significance (VUS) were confirmed in 10 individuals with suspected HHA. Of these variants, the p.Trp704Ter nonsense variant of EPB41 and missense p.Gly151Asp variant of SPTA1 were identified in two out of four hereditary elliptocytoses. The frameshift p.Leu884GlyfsTer27 variant of ANK1, nonsense p.Trp652Ter variant of the SPTB, and missense p.Arg490Trp variant of PKLR were detected in all four hereditary spherocytosis cases. Missense p.Glu27Lys, nonsense p.Lys18Ter variants, and splicing errors such as c.92 + 1G > T and c.315 + 1G > A within HBB were identified in four beta thalassemia cases.
CONCLUSIONS: This study provides a snapshot of the genetic alterations in a cohort of Korean HHA individuals and demonstrates the clinical utility of using gene panels in HHA. Genetic results can provide precise clinical diagnosis and guidance regarding medical treatment and management for some individuals.