title: Identification of a High-Frequency Somatic NLRC4 Mutation as a Cause of Autoinflammation by Pluripotent Cell-Based Phenotype Dissection.
abstract: To elucidate the genetic background of a patient with neonatal-onset multisystem inflammatory disease (NOMID) with no NLRP3 mutation.
  
  
  
  A Japanese male child diagnosed as having NOMID was studied. The patient did not have any NLRP3 mutation, even as low-frequency mosaicism. We performed whole-exome sequencing on the patient and his parents. Induced pluripotent stem cells (iPSCs) were established from the patient's fibroblasts. The iPSCs were then differentiated into monocyte lineage to evaluate the cytokine profile.
  
  
  
  We established multiple iPSC clones from a patient with NOMID and incidentally found that the phenotypes of monocytes from iPSC clones were heterogeneous and could be grouped into disease and normal phenotypes. Because each iPSC clone was derived from a single somatic cell, we hypothesized that the patient had somatic mosaicism of an interleukin-1β-related gene. Whole-exome sequencing of both representative iPSC clones and the patient's blood revealed a novel heterozygous NLRC4 mutation, p.T177A (c.529A>G), as a specific mutation in diseased iPSC clones. Knockout of the NLRC4 gene using the clustered regularly interspaced short palindromic repeat/Cas9 system in a mutant iPSC clone abrogated the pathogenic phenotype.
  
  
  
  Our findings indicate that the patient has somatic mosaicism of a novel NLRC4 mutation. To our knowledge, this is the first case showing that somatic mutation of NLRC4 causes autoinflammatory symptoms compatible with NOMID. The present study demonstrates the significance of prospective genetic screening combined with iPSC-based phenotype dissection for individualized diagnoses.
authors: Kyoto University, Kyoto, Japan.
authors: Yuri
authors: Y
authors: Kawasaki
authors: Kyoto University, Kyoto, Japan, and RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
authors: Hirotsugu
authors: H
authors: Oda
authors: Kyoto University, Kyoto, Japan.
authors: Jun
authors: J
authors: Ito
authors: Kyoto University, Kyoto, Japan.
authors: Akira
authors: A
authors: Niwa
authors: Kyoto University, Kyoto, Japan.
authors: Takayuki
authors: T
authors: Tanaka
authors: Nagahama Institute of Bio-Science and Technology, Nagahama, Japan.
authors: Atsushi
authors: A
authors: Hijikata
authors: Kyoto University and Nippon Shinyaku Company, Ltd., Kyoto, Japan.
authors: Ryosuke
authors: R
authors: Seki
authors: Kyoto University, Kyoto, Japan.
authors: Ayako
authors: A
authors: Nagahashi
authors: Kyoto University, Kyoto, Japan.
authors: Mitsujiro
authors: M
authors: Osawa
authors: Kyoto University, Kyoto, Japan.
authors: Isao
authors: I
authors: Asaka
authors: Kyoto University, Kyoto, Japan.
authors: Akira
authors: A
authors: Watanabe
authors: Tokyo Medical University, Tokyo, Japan.
authors: Shigeo
authors: S
authors: Nishimata
authors: Nagahama Institute of Bio-Science and Technology, Nagahama, Japan.
authors: Tsuyoshi
authors: T
authors: Shirai
authors: Tokyo Medical University, Tokyo, Japan.
authors: Hisashi
authors: H
authors: Kawashima
authors: RIKEN Center for Integrative Medical Sciences, Yokohama, Japan, and Kazusa DNA Research Institute, Kisarazu, Japan.
authors: Osamu
authors: O
authors: Ohara
authors: Kyoto University, Kyoto, Japan.
authors: Tatsutoshi
authors: T
authors: Nakahata
authors: Kyoto University, Kyoto, Japan.
authors: Ryuta
authors: R
authors: Nishikomori
authors: Kyoto University, Kyoto, Japan.
authors: Toshio
authors: T
authors: Heike
authors: Kyoto University, Kyoto, Japan.
authors: Megumu K
authors: MK
authors: Saito
mesh_terms: D053468:CARD Signaling Adaptor Proteins / Q000235:genetics*; D002135:Calcium-Binding Proteins / Q000235:genetics*; D056587:Cryopyrin-Associated Periodic Syndromes / Q000235:genetics*; D006801:Humans; D057026:Induced Pluripotent Stem Cells; D007231:Infant, Newborn; D008297:Male; D009154:Mutation; D010641:Phenotype
chemical_list: D053468:CARD Signaling Adaptor Proteins; D002135:Calcium-Binding Proteins; C435692:NLRC4 protein, human