Table 2.
Clinical feature frequency in individuals with HDAC8 mutations
| Category | Feature | Percent (no. observed/no. assessed) | Details |
|---|---|---|---|
| Head | Brachycephaly | 70% (24/34) | |
| Low anterior hairline | 67% (23/34) | ||
| Skull | Prominent metopic suture (1), open/delayed fontanelles (13), asymmetry (2) | ||
| Eyes | Arched eyebrows | 88% (30/34) | |
| Synophrys | 90% (30/33) | ||
| Long eyelashes | 45% (14/31) | ||
| Hypertelorism | 47% (16/34) | ||
| Telecanthus | 64% (22/34) | ||
| Ptosis | 18% (6/32) | ||
| Myopia | 44% (11/25) | ||
| Lacrimal duct obstruction | 24% (6/25) | ||
| Hooding of lids | 46% (15/32) | ||
| Nose | Depressed nasal bridge | 45% (15/33) | |
| Anteverted nostrils | 76% (26/34) | ||
| Long philtrum | 57% (19/33) | ||
| Featureless philtrum | 30% (10/33) | ||
| Broad/bulbous nasal tip | 66% (22/33) | ||
| Mouth | Thin upper lip | 29% (10/34) | |
| Downturned corners of mouth | 57% (19/33) | ||
| Palate—high arch | 33% (7/21) | ||
| Palate—cleft | 18% (5/27) | ||
| Widely spaced teeth | 61% (16/26) | ||
| Gap between upper incisors | 50% (13/26) | ||
| Other teeth | (19) | Congenital abnormalities (10), oligodontia (3), fused (4), delayed (6) | |
| Micrognathia/retrognathia | 59% (19/32) | ||
| Short neck | 48% (12/25) | ||
| Other facial | Facial asymmetry (2), grimacing smile (1), small low-set ears (5), macrostomia (1), premature aging (1) | ||
| Skin | Cutis marmorata | 18% (5/27) | |
| Hirsutism | 65% (21/32) | ||
| Nevus flammeus | 58% (17/29) | ||
| Other skin | Pigmentary mosaicism (6), slow-growing hair and nails (1) | ||
| Hands | Small hands | 96% (28/29) | |
| Proximally set thumbs | 85% (23/27) | ||
| Clinodactyly 5th finger | 50% (14/28) | ||
| Short 5th finger | 84% (21/25) | ||
| Single Palmar crease | 20% (5/24) | ||
| Feet | Small feet | 89% (26/29) | |
| Syndactyly of toes | 44% (12/27) | ||
| Arms | Restriction of elbow movements | 4% (1/23) | |
| Other skeletal | Atypical/absent patella (2) | ||
| Cardiac | Cardiac defects | Leg asymmetry (5), Short 4/5 metacarpals, 5th fingers and distal (6), phalanges of thumbs | |
| Genitourinary | Genitourinary defects | 36% (11/30) | |
| Gastrointestinal | GER | 44% (13/29) | VUR/hydronephrosis (6), renal cysts (2), dysplasia (2), chronic disease (2), cryptorchidism or hypoplastic genitalia (5/8 males) PCOS (2) |
| Feeding problems in infancy | 67% (19/28) | ||
| GI anomalies | 86% (25/29) | ||
| Other gastrointestinal | |||
| Otolaryngologic | Hearing loss | 59% (16/27) | |
| CNS | CNS anomalies | 22% (6/27) | |
| Seizures | 28% (8/28) | ||
| Other | Hypertonia (3), hypotonia (1), gait apraxia (1) | ||
| Cognitive | Intellectual disability | 100% (30/30) | Carrier mothers not carefully evaluated |
| Behavior, personality | (23) | Autistic (3), friendly (14), hyperactive (3), aggressive (3 older), self-injurious (3) |
Clinical features are summarized by category. Percent and fractional data are indicated. Single numbers in parentheses indicate the number assessed or noted with the feature. M, male; F, female; PCOS, polycystic ovarian syndrome; GER, gastroesophageal reflux; CNS, central nervous system; VUR, vesicoureteral reflux.