PUBLICATION
Multisystem Anomalies in Severe Combined Immunodeficiency with Mutant BCL11B
- Authors
- Punwani, D., Zhang, Y., Yu, J., Cowan, M.J., Rana, S., Kwan, A., Adhikari, A.N., Lizama, C.O., Mendelsohn, B.A., Fahl, S.P., Chellappan, A., Srinivasan, R., Brenner, S.E., Wiest, D.L., Puck, J.M.
- ID
- ZDB-PUB-161215-12
- Date
- 2016
- Source
- The New England Journal of Medicine 375: 2165-2176 (Journal)
- Registered Authors
- Wiest, David
- Keywords
- none
- MeSH Terms
-
- Repressor Proteins/deficiency
- Repressor Proteins/genetics*
- Repressor Proteins/metabolism
- Severe Combined Immunodeficiency/genetics*
- Animals
- PubMed
- 27959755 Full text @ N. Engl. J. Med.
Abstract
Background Severe combined immunodeficiency (SCID) is characterized by arrested T-lymphocyte production and by B-lymphocyte dysfunction, which result in life-threatening infections. Early diagnosis of SCID through population-based screening of newborns can aid clinical management and help improve outcomes; it also permits the identification of previously unknown factors that are essential for lymphocyte development in humans. Methods SCID was detected in a newborn before the onset of infections by means of screening of T-cell-receptor excision circles, a biomarker for thymic output. On confirmation of the condition, the affected infant was treated with allogeneic hematopoietic stem-cell transplantation. Exome sequencing in the patient and parents was followed by functional analysis of a prioritized candidate gene with the use of human hematopoietic stem cells and zebrafish embryos. Results The infant had "leaky" SCID (i.e., a form of SCID in which a minimal degree of immune function is preserved), as well as craniofacial and dermal abnormalities and the absence of a corpus callosum; his immune deficit was fully corrected by hematopoietic stem-cell transplantation. Exome sequencing revealed a heterozygous de novo missense mutation, p.N441K, in BCL11B. The resulting BCL11B protein had dominant negative activity, which abrogated the ability of wild-type BCL11B to bind DNA, thereby arresting development of the T-cell lineage and disrupting hematopoietic stem-cell migration; this revealed a previously unknown function of BCL11B. The patient's abnormalities, when recapitulated in bcl11ba-deficient zebrafish, were reversed by ectopic expression of functionally intact human BCL11B but not mutant human BCL11B. Conclusions Newborn screening facilitated the identification and treatment of a previously unknown cause of human SCID. Coupling exome sequencing with an evaluation of candidate genes in human hematopoietic stem cells and in zebrafish revealed that a constitutional BCL11B mutation caused human multisystem anomalies with SCID and also revealed a prethymic role for BCL11B in hematopoietic progenitors. (Funded by the National Institutes of Health and others.).
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping