Table 1.
Clinical Presentation and SLC35A2 Mutations Identified in Three Families with CDG Type IIx
| CDG-341 | CDG-348 | CDG-352 | |
|---|---|---|---|
| Ancestry | European | European | European |
| Gender | Male | Female | Male |
| Current Age | 3 years | 3 years | 6 years |
| Inheritance | de novo | de novo | de novo |
| Nucleotide Change | chrX: 48,768,775_48,768,899 delinsT |
chrX: 48,768,911 C>T |
chrX: 48,762,195 C>T |
| cDNA Change | c.15_91+48 delinsA | c.3G>A | c.991G>A |
| Protein Change | p.Gly8Serfs∗9 | p.Met1? | p.Val331Ile |
| Likely Affect on Protein | Termination | Loss of initiator methionine | Improper positioning in membrane |
| Developmental Delay | Yes | Yes | Yes |
| Hypotonia | Yes | Yes | Yes |
| Seizures | Yes | Yes | No |
| Hypsarrhythmia | Yes | Yes | No |
| Hypertension | No | No | Yes |
| Dysmorphic features | No | Yes | Yes |
| Skeletal abnormalities | No | Shortened extremities | Shortened extremities |
| Renal | No | No | Acute nephrotic syndrome; requiring dialysis |
| Ocular | Nystagmus | Retinitis pigmentosa | Ocular flutter |
| Liver dysfunction | No | No | No |
| Coagulopathy | Yes | No | No |
| Gastrointestinal | No | Strictly G-tube feed | Gastro-esophageal reflux, esophagitis, duodenal perforation |
| Recurrent Infections | No | Yes | No |
| Microcephaly | No | Yes | Yes |
| Brain malformation | Small cerebellum | Thinning of corpus callosum with delayed myelinization | Cerebral hypoplasia/atrophy |