Phenotypes associated with the disease developmental delay with hypotonia, myopathy, and brain abnormalities (OMIM:620240):
- Narrow forehead (HP:0000341): Width of the forehead or distance between the frontotemporales is more than two standard deviations below the mean (objective); or apparently narrow intertemporal region (subjective). Evidence: PCS. Frequency: 1/1. (PMID:34424553)
- Hypsarrhythmia (HP:0002521): Hypsarrhythmia is abnormal interictal high amplitude waves and a background of irregular spikes. There is continuous (during wakefulness), high-amplitude (>200 Hz), generalized polymorphic slowing with no organized background and multifocal spikes demonstrated by electroencephalography (EEG). Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- Tented upper lip vermilion (HP:0010804): Triangular appearance of the oral aperture with the apex in the midpoint of the upper vermilion and the lower vermilion forming the base. Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- Elevated circulating creatine kinase activity (HP:0003236): The activity of creatine kinase in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:30237576)
- Clonus (HP:0002169): A series of rhythmic and involuntary muscle contractions (at a frequency of about 5 to 7 Hz) that occur in response to an abruptly applied and sustained stretch. Evidence: PCS. Frequency: 1/1. (PMID:30237576)
- 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: 1/1. (PMID:26742501)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 2/2. (PMID:30237576;PMID:26742501)
- 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: PCS. Frequency: 1/1. (PMID:30237576)
- Cerebral cortical atrophy (HP:0002120): Atrophy of the cortex of the cerebrum. Evidence: PCS. Frequency: 1/1. (PMID:34424553)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: PCS. Frequency: 3/3. (PMID:30237576;PMID:26742501;PMID:34424553)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 2/2. (PMID:26742501;PMID:34424553)
- Muscle fiber atrophy (HP:0100295). Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- Brain atrophy (HP:0012444): Partial or complete wasting (loss) of brain tissue that was once present. Evidence: PCS. Frequency: 1/1. (PMID:30237576)
- Thin corpus callosum (HP:0033725): An abnormally thin corpus callous, due to atrophy, hypoplasia or agenesis. This term is intended to be used in situations where it is not known if thinning of the corpus callosum (for instance, as visualized by magnetic resonance tomography) is due to abnormal development (e.g. a leukodystrophy) or atrophy following normal development (e.g. neurodegeneration). Evidence: PCS. Frequency: 3/3. (PMID:30237576;PMID:26742501;PMID:34424553)
- Infantile spasms (HP:0012469): Infantile spasms represent a subset of "epileptic spasms". Infantile Spasms are epileptic spasms starting in the first year of life (infancy). Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- Smooth philtrum (HP:0000319): Flat skin surface, with no ridge formation in the central region of the upper lip between the nasal base and upper vermilion border. Evidence: PCS. Frequency: 1/1. (PMID:34424553)
- Prominent forehead (HP:0011220): Forward prominence of the entire forehead, due to protrusion of the frontal bone. Evidence: PCS. Frequency: 1/1. (PMID:34424553)
- Progressive microcephaly (HP:0000253): Progressive microcephaly is diagnosed when the head circumference falls progressively behind age- and gender-dependent norms. Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: PCS. Frequency: 2/2. (PMID:30237576;PMID:34424553)
- Delayed speech and language development (HP:0000750): A degree of language development that is significantly below the norm for a child of a specified age. Evidence: PCS. Frequency: 1/1. (PMID:30237576)
- Global developmental delay (HP:0001263): A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age. Evidence: PCS. Frequency: 3/3. (PMID:30237576;PMID:26742501;PMID:34424553)
- Depressed nasal bridge (HP:0005280): Posterior positioning of the nasal root in relation to the overall facial profile for age. Evidence: PCS. Frequency: 1/1. (PMID:34424553)
- Autosomal recessive inheritance (HP:0000007): 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 individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:26742501)
- Focal-onset seizure (HP:0007359): A focal-onset seizure is a type of seizure originating within networks limited to one hemisphere. They may be discretely localized or more widely distributed, and may originate in subcortical structures. Evidence: PCS. Frequency: 1/1. (PMID:34424553)
- Micrognathia (HP:0000347): Developmental hypoplasia of the mandible. Evidence: PCS. Frequency: 1/1. (PMID:26742501)
- 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: 1/1. (PMID:26742501)