Table 2. Clinical features of Malan syndrome patients with pathogenic NFIX variants and deletions reported here and in the literature.
| All | Deletion of NFIX and other genes including CACNA1A | Deletion of NFIX excluding CACNA1A | Nonsense or frameshift NFIX variant | Missense or in-frame NFIX variant | |
|---|---|---|---|---|---|
| Number of patients | 20 | 8 | 6 | 3 | 3 |
| Median birthweight (SD) | +0.3 | 0 | +0.9 | +0.2 | −0.4 |
| Median length/height (SD)a | +2.0 | +1.4 | +1.7 | +2.5 | +3.8 |
| Median weight (SD)a | +0.6 | +1.2 | +1.2 | +1.3 | +0.6 |
| Median OFC (SD)a | +2.3 | +2.1 | +2.3 | +2.5 | +2.8 |
| Developmental delay | |||||
| Mild | 1 (5%) | 0 | 0 | 0 | 1 |
| Moderate | 15 (75%) | 7 | 5 | 2 | 1 |
| Severe | 4 (20%) | 1 | 1 | 1 | 1 |
| Neonatal feeding difficulties/hypotonia | 6/20 (30%) | 2/8 | 3/6 | 0/3 | 1/3 |
| Seizures | 5/20 (25%) | 1/8 | 3/6 | 0/3 | 1/3 |
| Episodic ataxia | 1/20 (5%) | 1/8 | 0/6 | 0/3 | 0/3 |
| Migraine | 1/20 (5%) | 1/8 | 0/6 | 0/3 | 0/3 |
| Nystagmus | 5/20 (25%) | 2/8 | 1/6 | 1/3 | 1/3 |
| Strabismus | 13/20 (65%) | 5/8 | 4/6 | 2/3 | 2/3 |
| Optic disc pallor/hypoplasia | 5/20 (25%) | 1/8 | 3/6 | 0/3 | 1/3 |
| Advanced bone age | 6/7 (86%) | 1/1 | 2/3 | 2/2 | 2/2 |
| Scoliosis | 5/20 (25%) | 0/8 | 2/6 | 1/3 | 2/3 |
| Pectus excavatum | 8/20 (40%) | 2/8 | 3/6 | 1/3 | 2/3 |
Abbreviations: OFC, occipital-frontal circumference; N/A, not available; SD, standard deviations above (+) or below (−) mean.
Genomic positions are given according to the HG19 build.
a
Measurement at last assessment in clinic.