Clinical data from female patients with a MECP2 gene mutation
| Case 1 | Case 2 | Case 3 | Case 4 | Case 5 | |
| OFC at birth | M | ? | −2 SD | M | −1 SD |
| Acquired microcephaly | −2 SD at 2 y | −1.5 SD at 2 y | −2 SD at 18 mth | −2 SD at 2 y | −4 SD at 3.5 y |
| Psychomotor development until 6 months | Mild hypotonia | ? | ? | Mild hypotonia | Hypotonia, poor contact from birth |
| Loss of purposeful hand skills | — | ? | + at 18 mth | + at 2 y | Never acquired |
| Hand stereotypies | + | ++ | ++ | ++ | ++ |
| Social contact | Poor/bursts of laughter | Poor/bursts of laugher | Inappropriate smile | Poor/inappropriate smile | Absent |
| Truncal ataxia and apraxia of gait | + | + | ++ | ++ | Poor spontaneous movements |
| Hyperpnoea | — | — | — | — | — |
| EEG anomalies/epilepsy | — | Bradyarrythmia/ paroxysmal anomalies | Paroxysmal anomalies | — | Bradyarrythmia/ paroxysmal anomalies |
| Spasticity | — | + | + | — | + |
| Kyphoscoliosis | — | + | — | — | ++ |
| Growth retardation | — | — | — | — | −2 SD |