title: Characterization of a novel disease-causing mutation in exon 1 of SH2D1A gene through amplicon sequencing: a case report on HLH.
abstract: BACKGROUND
  Hemophagocytic lymphohistocytosis (HLH) is a rare but fatal hyperinflammatory syndrome caused by uncontrolled proliferation of activated macrophages and T lymphocytes secreting high amounts of inflammatory cytokines. Genetic defect is a common cause of HLH. HLH is complicated to be diagnosed as there are many common symptoms with other disorders.
  
  
  METHODS
  Here we report on an HLH case caused by 1 bp deletion in gene SH2D1A. Patient was a 3-years-old boy and had fever for more than 8 days. Splenomegaly and hemophagocytosis in bone marrow were observed in examination. The results of the blood analysis suggested the diagnosis of HLH. Genetic test based on high throughput amplicon sequencing was then conducted by targeting all six known HLH-causing genes simultaneously. It took only one single day to accomplish the amplicon sequencing library preparation, sequencing and data analysis. Finally, a novel 1 bp deletion in gene SH2D1A was discovered. The result was also confirmed by Sanger sequencing. The result of the genetic test served as a good basis for further diagnosis of HLH.
  
  
  CONCLUSIONS
  This is the first case that the disease-causing genetic defect of HLH was quickly determined by high throughput amplicon sequencing. This diagnosis was also confirmed by Sanger sequencing and cross-validated by blood analysis and other clinical criteria. This case suggests that genetic test based on amplicon sequencing is a powerful tool for diagnosis of HLH and other diseases caused by genetic defect.
authors.affiliation: Henan Research Institute for Population and Family Planning, Zhengzhou, China.|Key Laboratory of Birthdefects Prevention, National Health and Family Planning Commission, #26 Jingwu Road, Zhengzhou, Henan, China.
authors.forename: Shiyuan
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Thermo Fisher Scientific, Building 6, N0.27, Xin Jinqiao Rd, Pudong, Shanghai, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Ma
authors.affiliation: Department of Laboratory Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Gao
authors.affiliation: Department of Clinical Medicine, Zhengzhou University, No.100 Science Avenue, Zhengzhou, China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Fang
authors.affiliation: Department of Clinical Medicine, Zhengzhou University, No.100 Science Avenue, Zhengzhou, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Thermo Fisher Scientific, Building 6, N0.27, Xin Jinqiao Rd, Pudong, Shanghai, China. qing.zhang@thermofisher.com.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Institute of System Biology, Jianghan University, Sanjiaohu Rd, Wuhan, Hubei, China. fangzhiwei1126@126.com.
authors.forename: GaoFu
authors.initials: G
authors.lastname: Qi
mesh_terms: D001483:Base Sequence; D001853:Bone Marrow / Q000473:pathology; D002675:Child, Preschool; D004247:DNA / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D005091:Exons; D017353:Gene Deletion; D005820:Genetic Testing; D006801:Humans; D051359:Lymphohistiocytosis, Hemophagocytic / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D017422:Sequence Analysis, DNA; D000071179:Signaling Lymphocytic Activation Molecule Associated Protein / Q000235:genetics*
chemical_list: C114953:SH2D1A protein, human; D000071179:Signaling Lymphocytic Activation Molecule Associated Protein; D004247:DNA
keywords: Amplicon sequencing; Genetic analysis; HLH; Mutation; SH2D1A