Phenotypes associated with the disease megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome 1 (OMIM:603387):
- Megalencephaly (HP:0001355): Diffuse enlargement of the entire cerebral hemispheres leading to macrocephaly (with or without overlying cortical dysplasia). Evidence: TAS. (OMIM:603387)
- 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: TAS. (OMIM:603387)
- Profound intellectual disability (HP:0002187): Profound intellectual disability (ID) is defined as a type of ID characterized by profoundly sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) below 20. Evidence: TAS. (OMIM:603387)
- Abnormally large globe (HP:0001090): Diffusely large eye (with megalocornea) without glaucoma. Evidence: TAS. (OMIM:603387)
- Ventricular septal defect (HP:0001629): A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum. Evidence: TAS. (OMIM:603387)
- Blindness (HP:0000618): Blindness is the condition of lacking visual perception defined as a profound reduction in visual perception. On the 6m visual acuity scale, blindness is defined as less than 3/60. On the 20ft visual acuity scale, blindness is defined as less than 20/400. On the decimal visual acuity scale, blindness is defined as less than 0.05. Blindness is typically characterized by a visual field of no greater than 10 degrees in radius around central fixation. Evidence: TAS. (OMIM:603387)
- Overgrowth (HP:0001548): Excessive postnatal growth which may comprise increased weight, increased length, and/or increased head circumference. Evidence: PCS. Frequency: 2/11. (PMID:22729224)
- 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: PCS. Frequency: 13/13. (PMID:22729224)
- Long palpebral fissure (HP:0000637): Distance between medial and lateral canthi is more than two standard deviations above the mean for age (objective); or, apparently increased length of the palpebral fissures. Evidence: TAS. (OMIM:603387)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: PCS. Frequency: 13/13. (PMID:22729224)
- Pachygyria (HP:0001302): Pachygyria is a malformation of cortical development with abnormally wide gyri with sulci 1,5-3 cm apart and abnormally thick cortex measuring more than 5 mm (radiological definition). See also neuropathological definitions for 2-, 3-, and 4-layered lissencephaly. Evidence: TAS. (OMIM:603387)
- 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: TAS. (OMIM:603387)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: TAS. (OMIM:603387)
- Skeletal muscle atrophy (HP:0003202): The presence of skeletal muscular atrophy (which is also known as amyotrophy). Evidence: TAS. (OMIM:603387)
- 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:22729224)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: TAS. (OMIM:603387)
- 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: TAS. (OMIM:603387)
- Vascular ring (HP:0010775): A developmental defect of the aortic arch system in which the trachea and esophagus are completely encircled by connected segments of the aortic arch and its branches. This occurs if the normal process of regression and persistence of the bilateral embryonic aortic arches fails. Evidence: TAS. (OMIM:603387)
- Postaxial polydactyly (HP:0100259): A form of polydactyly in which the extra digit or digits are localized on the side of the fifth finger or fifth toe. Evidence: PCS. Frequency: 2/13. Onset: Congenital onset (HP:0003577). (PMID:22729224)
- Knee flexion contracture (HP:0006380): A type of knee joint contracture in which the knee is in a fixed bent (flexed) configuration such that it cannot be straightened actively or passively. Evidence: TAS. (OMIM:603387)
- Thick corpus callosum (HP:0007074): Increased vertical dimension of the corpus callosum. This feature can be visualized by sagittal sections on magnetic resonance tomography imaging of the brain. Evidence: TAS. (OMIM:603387)
- Kyphosis (HP:0002808): Exaggerated anterior convexity of the thoracic vertebral column. Evidence: TAS. (OMIM:603387)
- Ptosis (HP:0000508): The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective). Evidence: TAS. (OMIM:603387)
- Frontal bossing (HP:0002007): Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline. Evidence: TAS. (OMIM:603387)
- Atrial septal defect (HP:0001631): Atrial septal defect (ASD) is a congenital abnormality of the interatrial septum that enables blood flow between the left and right atria via the interatrial septum. Evidence: TAS. (OMIM:603387)
- Mitral regurgitation (HP:0001653): An abnormality of the mitral valve characterized by insufficiency or incompetence of the mitral valve resulting in retrograde leaking of blood through the mitral valve upon ventricular contraction. Evidence: TAS. (OMIM:603387)
- Thoracic scoliosis (HP:0002943). Evidence: TAS. (OMIM:603387)
- 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:22729224)
- Polymicrogyria (HP:0002126): Polymicrogyria is a congenital malformation of the cerebral cortex characterized by abnormal cortical layering (lamination) and an excessive number of small gyri (folds). Evidence: PCS. Frequency: 13/13. (PMID:22729224)