Severe Combined Immune Deficiency (SCID), DCLRE1C Type

DCLRE1C mutations cause a T and B cell deficient form of SCID that is clinically indistinguishable from a RAG1/RAG2 disorder. Infants present with severe recurrent viral, bacterial or fungal infections and failure-to-thrive. All three genes encode enzymes required for VDJ recombination in T and B cells during lymphocyte maturation. Defects in DCLRE1C should be distinguished from RAG defects because the former have an additional feature, increased sensitivity to ionizing radiation. Additionally, both RAG and DCLRE1C disorders can present as Omenn syndrome, with residual levels of oligoclonal T cells, erythroderma and eosinophilia