Table 1.
Phenotype associated with homozygous PTRH2 mutation
| Pedigree ID (gender) | II.1 (f) | II.4 (m) | ||
|---|---|---|---|---|
| Age at last assessment (years) | 14.8 | 6.3 | ||
| Category | Feature | HPO1 | ||
| Growth | ||||
| Height | Postnatal growth retardation (years at onset) | 0008897 | + (11.4) | + (4) |
| Weight | Failure to thrive (years at onset) | 0001508 | + (11.4) | + (2.5) |
| Head and Neck | ||||
| Head | Postnatal microcephaly (OFC < P3; years at onset) | 0005484 | + (2.5) | + (0.3) |
| Brachycephaly | 0000248 | + | + | |
| Face | Abnormality of the midface | 0000309 | + | + |
| Myopathic facies | 0002058 | + | + | |
| Ears | Sensorineural hearing impairment | 0000407 | + | + |
| Eyes | Hypertelorism | 0000316 | + | + |
| Exotropia | 0000577 | + | + | |
| Mouth | Thin upper lip vermilion | 0000219 | + | + |
| Abdomen | ||||
| Liver | Hepatomegaly | 0002240 | − | + |
| Hepatic fibrosis or steatosis (on ultrasound) | 0001395/0001397 | + | + | |
| Pancreas | Exocrine pancreatic insufficiency | 0001738 | + | + |
| Pancreatic fibrosis (on ultrasound) | 0100732 | + | − | |
| Genitourinary | ||||
| External genitalia | Shawl scrotum | 0000049 | + | |
| Skeletal | ||||
| Pelvis | Congenital hip dislocation | 0001374 | + | − |
| Hands | Proximal placement of thumb | 0009623 | + | + |
| Long fingers | 0100807 | + | − | |
| Ulnar deviation of the 2nd and 3rd finger | 0009464, 0009463 | + | − | |
| Feet | Abnormality of the hallux | 0001844 | + | − |
| Talipes equinovalgus (incipient) | 0001772 | + | − | |
| Achilles tendon contracture | 0001771 | + | − | |
| Muscle, soft tissue | ||||
| Distal muscle weakness | 0002460 | + | + | |
| Skeletal muscle fibrosis (on ultrasound) | – | + | − | |
| Neurologic | ||||
| Central nervous system | Neonatal hypotonia | 0001319 | + | − |
| Motor delay | 0001270 | + | + | |
| Intellectual disability, moderate (IQ 39–45) | 0002342 | + (48) | + (39) | |
| Dysmetria | 0001310 | + | ||
| Ataxia | 0001251 | + | + | |
| Cerebellar hypoplasia (progressive) | 0001321 | + | + | |
| EEG abnormality: alpha-beta-waves even in sleep | 0002353 | + | + | |
| Peripheral nervous system | Demyelinating peripheral neuropathy (sensorimotor) | 0007108 | + | + |
| Endocrine features | ||||
| Hypothyroidism | 0000821 | + | + | |
| Prenatal manifestations | ||||
| Movement | Decreased fetal movement | 0001558 | + | − |
m, male; f, female; PTRH2, peptidyl-tRNA hydrolase 2; EEG, electroencephalogram; HPO, human phenotype ontology, OFC, occipito-frontal head circumference; P, percentile.
1
All symptoms are listed according to the nomenclature and the systematics of the Online Mendelian Inheritance in Man (OMIM) “Clinical Synopsis” and the Human Phenotype Ontology (HPO).22 The IQ was evaluated using the Kaufmann Assessment Battery for Children (K-ABC) in II.1 and the Bayley Scales of Infant Development (BSID-II) for II.4.