- Facial palsy (HP:0010628): Facial nerve palsy is a dysfunction of cranial nerve VII (the facial nerve) that results in inability to control facial muscles on the affected side with weakness of the muscles of facial expression and eye closure. This can either be present in unilateral or bilateral form. Evidence: TAS. (OMIM:310400)
- Flexion contracture (HP:0001371): A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints. Evidence: TAS. (OMIM:310400)
- Pyloric stenosis (HP:0002021): Pyloric stenosis, also known as infantile hypertrophic pyloric stenosis, is an uncommon condition in infants characterized by abnormal thickening of the pylorus muscles in the stomach leading to gastric outlet obstruction. Clinically infants are well at birth. Then, at 3 to 6 weeks of age, the infants present with projectile vomiting, potentially leading to dehydration and weight loss. Evidence: IEA. (OMIM:310400)
- Severe muscular hypotonia (HP:0006829): A severe degree of muscular hypotonia characterized by markedly reduced muscle tone. Evidence: IEA. (OMIM:310400)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: PCS. (PMID:9931531)
- Caesarean section (HP:0011410): Delivery of a fetus through surgical incisions made through the abdominal wall (laparotomy) and the uterine wall (hysterotomy). Evidence: PCS. Frequency: 19/42. (PMID:9931531)
- Low 5-minute APGAR score (HP:0030919). Evidence: PCS. Frequency: 19/39. (PMID:9931531)
- Low 1-minute APGAR score (HP:0030918). Evidence: PCS. Frequency: 35/39. (PMID:9931531)
- Hydrocephalus (HP:0000238): Hydrocephalus is an active distension of the ventricular system of the brain resulting from inadequate passage of CSF from its point of production within the cerebral ventricles to its point of absorption into the systemic circulation. Evidence: IEA. (OMIM:310400)
- Dandy-Walker malformation (HP:0001305): A congenital brain malformation typically characterized by incomplete formation of the cerebellar vermis, dilation of the fourth ventricle, and enlargement of the posterior fossa. In layman's terms, Dandy Walker malformation is a cyst in the cerebellum (typically symmetrical) that is involved with the fourth ventricle. This may interfere with the ability to drain cerebrospinal fluid from the brain, resulting in hydrocephalus. Dandy Walker cysts are formed during early embryonic development, while the brain forms. The cyst in the cerebellum typically has several blood vessels running through it connecting to the brain, thereby prohibiting surgical removal. Evidence: PCS. Frequency: 1/45. (PMID:9931531)
- High palate (HP:0000218): Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective). Evidence: PCS. (PMID:9931531)
- Macrocephaly (HP:0000256): Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium. Evidence: IEA. (OMIM:310400)
- Elevated circulating hepatic transaminase concentration (HP:0002910): Elevations of the levels of SGOT and SGPT in the serum. SGOT (serum glutamic oxaloacetic transaminase) and SGPT (serum glutamic pyruvic transaminase) are transaminases primarily found in the liver and heart and are released into the bloodstream as the result of liver or heart damage. SGOT and SGPT are used clinically mainly as markers of liver damage. Evidence: PCS. Frequency: 6/45. (PMID:9931531)
- Premature birth (HP:0001622): The birth of a baby of less than 37 weeks of gestational age. Evidence: PCS. Frequency: 10/42. (PMID:9931531)
- Arachnodactyly (HP:0001166): Abnormally long and slender fingers (spider fingers). Evidence: PCS. Frequency: 9/21. (PMID:9931531)
- Narrow face (HP:0000275): Bizygomatic (upper face) and bigonial (lower face) width are both more than 2 standard deviations below the mean (objective); or, an apparent reduction in the width of the upper and lower face (subjective). Evidence: TAS. (OMIM:310400)
- Generalized muscle weakness (HP:0003324): Generalized weakness or decreased strength of the muscles, affecting both distal and proximal musculature. Evidence: TAS. (OMIM:310400)
- Polyhydramnios (HP:0001561): The presence of excess amniotic fluid in the uterus during pregnancy. Evidence: PCS. Frequency: 14/31. (PMID:9931531)
- Hypokinesia (HP:0002375): Abnormally diminished motor activity. In contrast to paralysis, hypokinesia is not characterized by a lack of motor strength, but rather by a poverty of movement. The typical habitual movements (e.g., folding the arms, crossing the legs) are reduced in frequency. Evidence: TAS. (OMIM:310400)
- Long face (HP:0000276): Facial height (length) is more than 2 standard deviations above the mean (objective); or, an apparent increase in the height (length) of the face (subjective). Evidence: PCS. (PMID:9931531)
- Slender toe (HP:0011308): Toes that are disproportionately narrow (reduced girth) for the hand/foot size or build of the individual. Evidence: TAS. (OMIM:310400)
- Areflexia (HP:0001284): Absence of neurologic reflexes such as the knee-jerk reaction. Evidence: PCS. Frequency: 18/29. (PMID:9931531)
- Tube feeding (HP:0033454): Feeding problem necessitating food and nutrient delivery via a tube. Evidence: PCS. (PMID:9931531)
- Diaphragmatic eventration (HP:0009110): A congenital failure of muscular development of part or all of one or both hemidiaphragms, resulting in superior displacement of abdominal viscera and altered lung development. Evidence: IEA. (OMIM:310400)
- X-linked recessive inheritance (HP:0001419): A mode of inheritance that is observed for recessive traits related to a gene encoded on the X chromosome. In the context of medical genetics, X-linked recessive disorders manifest in males (who have one copy of the X chromosome and are thus hemizygotes), but generally not in female heterozygotes who have one mutant and one normal allele. Evidence: PCS. (PMID:8640223)
- Decreased fetal movement (HP:0001558): An abnormal reduction in quantity or strength of fetal movements. Evidence: PCS. Frequency: 21/36. (PMID:9931531)
- High forehead (HP:0000348): An abnormally increased height of the forehead. Evidence: PCS. (PMID:9931531)
- Dental malocclusion (HP:0000689): Dental malocclusion refers to an abnormality of the occlusion, or alignment, of the teeth and the way the upper and lower teeth fit together, resulting in overcrowding of teeth or in abnormal bite patterns. Evidence: PCS. (PMID:9931531)
- Neonatal hypotonia (HP:0001319): Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period. Evidence: PCS. Frequency: 45/45. Onset: Congenital onset (HP:0003577). (PMID:9931531)
- Birth length greater than 97th percentile (HP:0003517). Evidence: PCS. Frequency: 25/36. (PMID:9931531)
- Dolichocephaly (HP:0000268): An abnormality of skull shape characterized by a increased anterior-posterior diameter, i.e., an increased antero-posterior dimension of the skull. Cephalic index less than 76%. Alternatively, an apparently increased antero-posterior length of the head compared to width. Often due to premature closure of the sagittal suture. Evidence: PCS. (PMID:9931531)
- Cryptorchidism (HP:0000028): Testis in inguinal canal. That is, absence of one or both testes from the scrotum owing to failure of the testis or testes to descend through the inguinal canal to the scrotum. Evidence: PCS. Frequency: 17/30. (PMID:9931531)
- Neonatal respiratory distress (HP:0002643): Respiratory difficulty as newborn. Evidence: PCS. Frequency: 33/41. (PMID:9931531)
- External ophthalmoplegia (HP:0000544): Paralysis of the external ocular muscles. Evidence: IEA. (OMIM:310400)
- Neck muscle weakness (HP:0000467): Decreased strength of the neck musculature. Evidence: IEA. (OMIM:310400)
- Respiratory failure requiring assisted ventilation (HP:0004887): A state of respiratory distress that requires a life saving intervention in the form of gaining airway access and instituting positive pressure ventilation. Evidence: IEA. Frequency: 28/35. (OMIM:310400)
These phenotypes are associated with the disease X-linked myotubular myopathy (OMIM:310400).