Table 1.
Clinical and molecular summary of patients
| Characteristics | Patient 1 | Patient 2 | Patient 3 |
| Age at evaluation (years) | 13 | 11 | 17 |
| cDNA change | c.1068A > C | c.991C > T | c.938T > G |
| Protein change | p.Lys356Asn | p.Arg331* | p.Leu313* |
| Inheritance | Maternal transmission | De novo | Maternal transmission |
| Skewed X inactivation | Yes (98%) | NA | Yes (100%) |
| Intellectual/developmental disability | Yes | Yes | No |
| Behavior abnormalities | Yes | NT | No |
| Facial dysmorphism | Mild | Mild | No |
| Hepatomegaly | No | Yes | No |
| Immunological phenotype | |||
| CA EBV infection | No | No | Yes |
| Other infections | No | No | Yes |
| CD4:CD8 ratio | NT | NT | Normal |
| CD4 counts | Normal | NT | Decreased |
| Serum transferrin IEF | Type 1: 2-sialo form: 5.0% (normal range: 0–2.6) | Type 1 | Type 1: 2-sialo form: 7.0% (normal range: 0–2.6) |
CA EBV, chronic active Epstein Barr virus; IEF, isoelectric focusing; NA, not applicable; NT, not tested.