Tamaki Kato
   Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine
   Position   Assistant Professor
Article types Original article
Language English
Peer review Peer reviewed
Title A synonymous splice site mutation in IL2RG gene causes late-onset combined immunodeficiency.
Journal Formal name:International journal of hematology
Abbreviation:Int J Hematol
ISSN code:18653774/09255710
Domestic / ForeginForegin
Volume, Issue, Page 109(5),pp.603-611
Author and coauthor Kato Tamaki
Publication date 2019/05
Summary X-Linked severe combined immunodeficiency (X-SCID) is a severe form of primary immunodeficiency characterized by absence of T cells and NK cells. X-SCID is caused by a loss-of-function mutation in the IL2RG gene that encodes common gamma chain (γc), which plays an essential role in lymphocyte development. We report the first case of hypomorphic X-SCID caused by a synonymous mutation in the IL2RG gene leading to a splice anomaly, in a family including two patients with diffuse cutaneous warts, recurrent molluscum contagiosum, and mild respiratory infections. The mutation caused aberrant splicing of IL2RG mRNA, subsequently resulted in reduced γc expression. The leaky production of normally spliced IL2RG mRNA produced undamaged protein; thus, T cells and NK cells were generated in the patients. Functional assays of the patients' T cells and NK cells revealed diminished cytokine response in the T cells and absent cytokine response in the NK cells. In addition, the TCR repertoire in these patients was limited. These data suggest that a fine balance between aberrant splicing and leaky production of normally spliced IL2RG mRNA resulted in late-onset combined immunodeficiency in these patients.
DOI 10.1007/s12185-019-02619-9
PMID 30850927