Phenotypes associated with the disease Joubert syndrome 2 (OMIM:608091):
- Hypoplasia of the brainstem (HP:0002365): Underdevelopment of the brainstem. Evidence: IEA. (OMIM:608091)
- 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: 1/13. (PMID:20036350)
- Renal insufficiency (HP:0000083): A reduction in the level of performance of the kidneys in areas of function comprising the concentration of urine, removal of wastes, the maintenance of electrolyte balance, homeostasis of blood pressure, and calcium metabolism. Evidence: PCS. Frequency: 2/13. (PMID:20036350)
- 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: 13/13. (PMID:20036350)
- Ataxia (HP:0001251): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: IEA. (OMIM:608091)
- Abnormal corpus callosum morphology (HP:0001273): Abnormality of the corpus callosum. Evidence: IEA. (OMIM:608091)
- Encephalocele (HP:0002084): A neural tube defect characterized by sac-like protrusions of the brain and the membranes that cover it through openings in the skull. Evidence: IEA. (OMIM:608091)
- Elongated superior cerebellar peduncle (HP:0011933): Increased length of the superior cerebellar peduncle. Evidence: TAS. (OMIM:608091)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: IEA. (OMIM:608091)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: PCS. (PMID:20036350)
- Abnormality of ocular smooth pursuit (HP:0000617): An abnormality of eye movement characterized by impaired smooth-pursuit eye movements. Evidence: IEA. (OMIM:608091)
- Oculomotor apraxia (HP:0000657): Ocular motor apraxia is a deficiency in voluntary, horizontal, lateral, fast eye movements (saccades) with retention of slow pursuit movements. The inability to follow objects visually is often compensated by head movements. There may be decreased smooth pursuit, and cancelation of the vestibulo-ocular reflex. Evidence: PCS. (PMID:20036350)
- 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: IEA. (OMIM:608091)
- Molar tooth sign on MRI (HP:0002419): An abnormal appearance of the midbrain in axial magnetic resonance imaging in which the elongated superior cerebellar peduncles give the midbrain an appearance reminiscent of a molar or wisdom tooth. Evidence: PCS. Frequency: 13/13. (PMID:20036350)
- 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: 1/13. (PMID:20036350)
- 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: IEA. (OMIM:608091)
- Episodic tachypnea (HP:0002876): Episodes of very rapid breathing. Evidence: IEA. (OMIM:608091)
- 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:608091)
- Retinal dystrophy (HP:0000556): Retinal dystrophy is an abnormality of the retina associated with a hereditary process. Retinal dystrophies are defined by their predominantly monogenic inheritance and they are frequently associated with loss or dysfunction of photoreceptor cells as a primary or secondary event. Evidence: IEA. (OMIM:608091)
- Intellectual disability (HP:0001249): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: PCS. Frequency: 13/13. (PMID:20036350)
- Agenesis of cerebellar vermis (HP:0002335): Congenital absence of the vermis of cerebellum. Evidence: PCS. (PMID:20036350)
- Abnormal foot morphology (HP:0001760): An abnormality of the skeleton of foot. Evidence: IEA. (OMIM:608091)
- Rotary nystagmus (HP:0001583): A form of nystagmus in which the eyeball makes rotary motions around the axis. Evidence: PCS. Frequency: 11/13. (PMID:20036350)
- Central apnea (HP:0002871): Apnea resulting from depression of the respiratory centers in the medulla oblongata. There is a lack of respiratory effort rather than obstruction of airflow. Evidence: IEA. (OMIM:608091)
- Postaxial hand polydactyly (HP:0001162): Supernumerary digits located at the ulnar side of the hand (that is, on the side with the fifth finger). Evidence: PCS. Frequency: 2/13. Onset: Congenital onset (HP:0003577). (PMID:20036350)
- Hypoplastic male external genitalia (HP:0000050): Underdevelopment of part or all of the male external reproductive organs (which include the penis, the scrotum and the urethra). Evidence: IEA. (OMIM:608091)
- 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: 13/13. (PMID:20036350)
- Dysgenesis of the cerebellar vermis (HP:0002195): Defective development of the vermis of cerebellum. Evidence: PCS. (PMID:20036350)
- Abnormal saccadic eye movements (HP:0000570): An abnormality of eye movement characterized by impairment of fast (saccadic) eye movements. Evidence: IEA. (OMIM:608091)
- Neonatal breathing dysregulation (HP:0002790). Evidence: IEA. (OMIM:608091)
- Nephronophthisis (HP:0000090): Presence of cysts at the corticomedullary junction of the kidney in combination with tubulointerstitial fibrosis. Evidence: IEA. (OMIM:608091)
- Depressed nasal bridge (HP:0005280): Posterior positioning of the nasal root in relation to the overall facial profile for age. Evidence: IEA. (OMIM:608091)
- Enlarged fossa interpeduncularis (HP:0100951). Evidence: PCS. (OMIM:608091)
- Metopic synostosis (HP:0011330): Premature fusion of the metopic suture. Evidence: PCS. Frequency: 1/13. (PMID:20036350)
- Brainstem dysplasia (HP:0002508): A developmental structural anomaly of the stalk-like part of the brain that comprises the midbrain (aka mesencephalon), the pons (aka pons Varolii), and the medulla oblongata, and connects the cerebral hemispheres with the cervical spinal cord. Evidence: IEA. (OMIM:608091)
- Renal cyst (HP:0000107): A fluid filled sac in the kidney. Evidence: IEA. (OMIM:608091)
- Impaired smooth pursuit (HP:0007772): An impairment of the ability to track objects with the ocular smooth pursuit system, a class of rather slow eye movements that minimizes retinal target motion. Evidence: TAS. (OMIM:608091)
- Microphthalmia (HP:0000568): A developmental anomaly characterized by abnormal smallness of one or both eyes. Evidence: IEA. (OMIM:608091)
- 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:20036350)
- 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: IEA. (OMIM:608091)
- Postaxial foot polydactyly (HP:0001830): Polydactyly of the foot most commonly refers to the presence of six toes on one foot. Postaxial polydactyly affects the lateral ray and the duplication may range from a well-formed articulated digit to a rudimentary digit. Evidence: PCS. Frequency: 3/13. Onset: Congenital onset (HP:0003577). (PMID:20036350)
- Frontal bossing (HP:0002007): Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline. Evidence: PCS. Frequency: 6/13. (PMID:20036350)
- Esotropia (HP:0000565): A form of strabismus with one or both eyes turned inward ('crossed') to a relatively severe degree, usually defined as 10 diopters or more. Evidence: PCS. Frequency: 5/13. (PMID:20036350)
- 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. Frequency: 6/13. (PMID:20036350)
- Thickened superior cerebellar peduncle (HP:0002404): Increased width of the superior cerebellar peduncle. Evidence: TAS. (OMIM:608091)
- Low-set ears (HP:0000369): Upper insertion of the ear to the scalp below an imaginary horizontal line drawn between the inner canthi of the eye and extending posteriorly to the ear. Evidence: IEA. (OMIM:608091)
- Chorioretinal coloboma (HP:0000567): Absence of a region of the retina, retinal pigment epithelium, and choroid. Evidence: IEA. (OMIM:608091)
- Optic disc coloboma (HP:0000588): A cleft of the optic nerve that extends inferiorly. Evidence: IEA. (OMIM:608091)