Defects in Other Lymphocyte-Specific Genes Leading to SCIDa
Lymphocytes Present | |||
---|---|---|---|
Disease | Genetic defect | T cells | B cells |
a Mutations, in some instances, may allow partial expression and function of certain immune cell lineages. | |||
b Absent or decreased numbers of CD8+ T cells with normal numbers of CD4+ T cells. | |||
CD3γ/CD3ε deficiency | Defective transcription of CD3D and CD3E genes | + | + |
CD8 deficiency | Mutation in CD8A gene | −b | + |
ZAP-70 deficiency | Mutation in ZAP-70 kinase gene | −b | + |
MHC II deficiency | Mutation in transcription factors for MHC II | −b | + |
TAP 1/2 deficiency | Mutation in TAP 1/2 genes: MHC I deficiency | −b | + |
X-linked hyper-IgM | Mutation in CD40 ligand gene: Defective B cells | + | +/− |
CD40 deficiency | Mutation in CD40 ligand gene: Defective B cells | + | +/− |
ORAI1 deficiency | Mutation in ORAI1 gene: Defective Ca2+ influx in T cells | + | + |