Table 1.
Frequency of major clinical findings associated with C-terminal truncations of MN1
| Phenotype | Affected individuals, n (%) |
|---|---|
| Hypertelorism | 19/21 (90) |
| Downslanting palpebral fissures | 15/21 (71) |
| Midface hypoplasia | 21/22 (95) |
| Cranial shape defects (plagiocephaly, brachycephaly, turricephaly, dolicocephaly, bitemporal narrowing) | 16/21 (76) |
| Short, upturned nose | 21/22 (95) |
| High-arched palate | 15/21 (71) |
| Dysplastic ears | 22/22 (100) |
| Hearing loss (conductive or sensorineural) | 16/20 (80) |
| Speech delay | 18/20 (90) |
| Intellectual disability | 16/17 (94) |
| Motor delay | 19/20 (95) |
| Feeding difficulties | 12/18 (67) |
| Hypotonia | 17/18 (94) |
Note that only Individuals 1–6 and 8–23 were considered for the frequencies listed (Individual 7 was excluded because mosaicism of the MN1 mutation).