- Strabismus (HP:0000486): A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error. Evidence: PCS. Frequency: 11/15. (PMID:31353023)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 5/16. (PMID:31353023)
- Inguinal hernia (HP:0000023): Protrusion of the contents of the abdominal cavity through the inguinal canal. Evidence: PCS. Frequency: 4/15. (PMID:31353023)
- Seizure (HP:0001250): A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Evidence: PCS. Frequency: 3/15. (PMID:31353023)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: PCS. Frequency: 6/14. (PMID:31353023)
- Agenesis of corpus callosum (HP:0001274): Absence of the corpus callosum as a result of the failure of the corpus callosum to develop, which can be the result of a failure in any one of the multiple steps of callosal development including cellular proliferation and migration, axonal growth or glial patterning at the midline. Evidence: PCS. Frequency: 1/16. (PMID:31353023)
- Gastroesophageal reflux (HP:0002020): A condition in which the stomach contents leak backwards from the stomach into the esophagus through the lower esophageal sphincter. Evidence: PCS. Frequency: 6/14. (PMID:31353023)
- Generalized hypotonia (HP:0001290): Generalized muscular hypotonia (abnormally low muscle tone). Evidence: PCS. Frequency: 14/15. (PMID:31353023)
- Enlarged cisterna magna (HP:0002280): Increase in size of the cisterna magna, one of three principal openings in the subarachnoid space between the arachnoid and pia mater, located between the cerebellum and the dorsal surface of the medulla oblongata. Evidence: PCS. Frequency: 1/16. (PMID:31353023)
- Developmental stagnation (HP:0007281): A cessation of the development of a child in the areas of motor skills, speech and language, cognitive skills, and social and/or emotional skills. Evidence: PCS. Frequency: 4/15. (PMID:31353023)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: PCS. Frequency: 3/15. (PMID:31353023)
- Hypertelorism (HP:0000316): Interpupillary distance more than 2 SD above the mean (alternatively, the appearance of an increased interpupillary distance or widely spaced eyes). Evidence: PCS. Frequency: 6/16. (PMID:31353023)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: PCS. Frequency: 5/16. (PMID:31353023)
- 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. Frequency: 5/14. (PMID:31353023)
- Delayed ability to sit (HP:0025336): A failure to achieve the ability to sit at an appropriate developmental stage. Most children sit with support at 6 months of age and sit steadily without support at 9 months of age. Evidence: PCS. (PMID:31353023)
- Exercise intolerance (HP:0003546): A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender. Evidence: PCS. Frequency: 10/14. (PMID:31353023)
- Skeletal muscle atrophy (HP:0003202): The presence of skeletal muscular atrophy (which is also known as amyotrophy). Evidence: PCS. Frequency: 4/15. (PMID:31353023)
- Typically de novo (HP:0025352): Description of conditions that are exclusively or predominantly observed to display de novo variants. In some cases, this may be due to the limited reproductive fitness of affected individuals. Evidence: PCS. (PMID:31353023)
- Cleft palate (HP:0000175): Cleft palate is a developmental defect of the palate resulting from a failure of fusion of the palatine processes and manifesting as a separation of the roof of the mouth (soft and hard palate). Evidence: PCS. Frequency: 1/14. (PMID:31353023)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: PCS. Frequency: 5/16. (PMID:31353023)
- Tooth malposition (HP:0000692): Abnormal alignment, positioning, or spacing of the teeth, i.e., misaligned teeth. Evidence: PCS. Frequency: 5/16. (PMID:31353023)
- Delayed ability to walk (HP:0031936): A failure to achieve the ability to walk at an appropriate developmental stage. Most children learn to walk in a series of stages, and learn to walk short distances independently between 12 and 15 months. Evidence: PCS. (PMID:31353023)
- Abnormal globus pallidus morphology (HP:0002453): An abnormality of the globus pallidus. Evidence: PCS. Frequency: 2/16. (PMID:31353023)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: PCS. Frequency: 2/16. (PMID:31353023)
- Feeding difficulties (HP:0011968): Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it. Evidence: PCS. Frequency: 10/14. (PMID:31353023)
- Frog-leg posture (HP:0031139): A type of rest posture in an infant that indicated a generalized reduction in muscle tone. The hips are flexed and the legs are abducted to an extent that causes the lateral thigh to rest upon the supporting surface. This posture is said to resemble the legs of a frog. Evidence: PCS. Frequency: 10/15. Onset: Infantile onset (HP:0003593). (PMID:31353023)
- Autistic behavior (HP:0000729): Persistent deficits in social interaction and communication and interaction as well as a markedly restricted repertoire of activity and interest as well as repetitive patterns of behavior. Evidence: PCS. Frequency: 4/14. (PMID:31353023)
- Pectus excavatum (HP:0000767): A defect of the chest wall characterized by a depression of the sternum, giving the chest ("pectus") a caved-in ("excavatum") appearance. Evidence: PCS. Frequency: 3/15. (PMID:31353023)
- High forehead (HP:0000348): An abnormally increased height of the forehead. Evidence: PCS. Frequency: 7/14. (PMID:31353023)
- Decreased fetal movement (HP:0001558): An abnormal reduction in quantity or strength of fetal movements. Evidence: PCS. Frequency: 3/15. Onset: Fetal onset (HP:0011461). (PMID:31353023)
- Visual impairment (HP:0000505): Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery. Evidence: PCS. Frequency: 5/15. (PMID:31353023)
- Recurrent respiratory infections (HP:0002205): An increased susceptibility to respiratory infections as manifested by a history of recurrent respiratory infections. Evidence: PCS. Frequency: 8/14. (PMID:31353023)
- Plagiocephaly (HP:0001357): Asymmetric head shape, which is usually a combination of unilateral occipital flattening with ipsilateral frontal prominence, leading to rhomboid cranial shape. Evidence: PCS. Frequency: 5/16. (PMID:31353023)
- Brachycephaly (HP:0000248): An abnormality of skull shape characterized by a decreased anterior-posterior diameter. That is, a cephalic index greater than 81%. Alternatively, an apparently shortened anteroposterior dimension (length) of the head compared to width. Evidence: PCS. Frequency: 5/16. (PMID:31353023)
- Autosomal dominant inheritance (HP:0000006): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: PCS. (PMID:31353023)
These phenotypes are associated with the disease neurodevelopmental disorder with hypotonia and variable intellectual and behavioral abnormalities (OMIM:618603).