{"Name":"NARP syndrome","DiseaseID__c":"GARD:0000262","id":262,"encodedName":"narp-syndrome","IsDeleted":false,"Disease_Name_Full__c":"NARP syndrome","Xref_IDs__c":"237984008; C1328349; C537396; DOID:0111273; MEDGEN:231285; MONDO:0010794; OMIM:551500; ORPHA:644","USA_Estimate__c":"50,000","No_of_Specialist_Tagsa__c":8,"No_of_ClinGen_records__c":0,"No_of_GeneReviews__c":0,"No_of_HHS_records__c":1,"World_Estimate__c":"80,000 to 800,000","No_of_HRSA_records__c":0,"Evidence_Based_Score__c":1,"No_of_Disease_Descriptions__c":3,"Disease_Characteristics_Score__c":8,"No_of_Age_at_Onset__c":1,"Description_Source__c":"MONDO:0010794","Disease_Description__c":"A clinically heterogeneous progressive condition characterized by a combination of proximal neurogenic muscle weakness, sensory-motor neuropathy, ataxia, and pigmentary retinopathy.","GARD_Name__c":"NARP syndrome","GARD_Synonym__c":"narp (neurogenic muscle weakness, ataxia, retinitis pigmentosa) syndrome; neurogenic muscle weakness-ataxia-retinitis pigmentosa syndrome; neurogenic muscle weakness, ataxia and retinitis pigmentosa; neuropathy-ataxia-retinitis pigmentosa syndrome","Curated_Disease_Description_Source__c":"GARD:0000262","Curated_Disease_Description__c":"Neuropathy, ataxia, and retinitis pigmentosa (NARP) is a condition that causes a variety of signs and symptoms that mainly affect the nervous system. The condition typically begins in childhood or early adulthood, and the signs and symptoms usually worsen over time. Most people with NARP experience numbness, tingling, or pain in the arms and legs (sensory neuropathy); muscle weakness; and problems with balance and coordination (ataxia). Many affected individuals also have vision loss caused by changes in the light-sensitive tissue that lines the back of the eye (the retina). In some cases, the vision loss results from a condition called retinitis pigmentosa. This eye disease causes the light-sensing cells of the retina gradually to deteriorate. Learning disabilities and developmental delays are often seen in children with NARP, and older individuals with this condition may experience a loss of intellectual function (dementia). Other features of NARP include seizures, hearing loss, and abnormalities of the electrical signals that control the heartbeat (cardiac conduction defects). These signs and symptoms vary among affected individuals.","Curated_USA_Estimate_Source__c":null,"Curated_USA_Estimate__c":"50,000","Age_at_Onset_Snippet_Text__c":"as a Child","SourceID__c":"ORPHA:644","Deprecated__c":"No","Disease_Concept_Type__c":"Rare Disease Entity","MONDO_ID__c":"MONDO:0010794","ORPHANET_ID__c":"ORPHA:644","Replaced_By_ID__c":null,"Display_Spanish_Disease_Name__c":"Síndrome de narp","Spanish_Description_Source__c":"ORPHA:644","Spanish_Description__c":"Es una condición progresiva clínicamente heterogénea caracterizada por una combinación de debilidad muscular neurogénica proximal, neuropatía sensitivo-motora, ataxia y retinopatía pigmentaria.","Spanish_Disease_Name__c":"síndrome de narp","Spanish_GARD_Synonym__c":"debilidad muscular neurogénica-ataxia-retinosis pigmentaria; neuropatía-ataxia-retinosis pigmentaria","Category_Linearization__c":"ORPHA:98006","icd10_id__c":null,"mesh_id__c":null,"omim_id__c":null,"snomed_id__c":null,"umls_id__c":null,"GARD_Disease__c":[{"Curated_Disease_Description__c":"Neuropathy, ataxia, and retinitis pigmentosa (NARP) is a condition that causes a variety of signs and symptoms that mainly affect the nervous system. The condition typically begins in childhood or early adulthood, and the signs and symptoms usually worsen over time. Most people with NARP experience numbness, tingling, or pain in the arms and legs (sensory neuropathy); muscle weakness; and problems with balance and coordination (ataxia). Many affected individuals also have vision loss caused by changes in the light-sensitive tissue that lines the back of the eye (the retina). In some cases, the vision loss results from a condition called retinitis pigmentosa. This eye disease causes the light-sensing cells of the retina gradually to deteriorate. Learning disabilities and developmental delays are often seen in children with NARP, and older individuals with this condition may experience a loss of intellectual function (dementia). Other features of NARP include seizures, hearing loss, and abnormalities of the electrical signals that control the heartbeat (cardiac conduction defects). These signs and symptoms vary among affected individuals.","Curated_Disease_Description_Source__c":"GARD:0000262","GARD_Synonym__c":"narp (neurogenic muscle weakness, ataxia, retinitis pigmentosa) syndrome; neurogenic muscle weakness-ataxia-retinitis pigmentosa syndrome; neurogenic muscle weakness, ataxia and retinitis pigmentosa; neuropathy-ataxia-retinitis pigmentosa syndrome","Name":"NARP syndrome","Curated_USA_Estimate__c":"50,000","estimateUsa":"50,000"}],"Organization_Supported_Diseases__c":[{"Account_Name__c":"Muscular Dystrophy Association","Website__c":"https://www.mda.org"},{"Account_Name__c":"Australian Mitochondrial Disease Foundation","Website__c":"https://www.amdf.org.au/"},{"Account_Name__c":"Metabolic Support UK","Website__c":"https://www.metabolicsupportuk.org"},{"Account_Name__c":"Childhood Dementia Initiative","Website__c":"https://www.childhooddementia.org/"},{"Account_Name__c":"MitoAction","Website__c":"https://www.mitoaction.org/"},{"Account_Name__c":"United Mitochondrial Disease Foundation","Website__c":"https://www.umdf.org"},{"Account_Name__c":"Retina International","Website__c":"https://retina-international.org/"}],"GARD_Disease_Tag__c":[{"Tag_Name__c":"Genetics","Tag_Category__c":"Cause;Disease Category;Specialist","category_description":"Genetic diseases affect the DNA, or genetic instructions, which directs how tissues, organs, and body systems function.","curated_tag_name":"Genetic diseases"},{"Tag_Name__c":"Neurology","Tag_Category__c":"Disease Category;Specialist","category_description":"Neurological diseases affect the brain, spinal cord, cranial nerves, autonomic nerves, or other peripheral nerves.","curated_tag_name":"Neurological diseases"},{"Tag_Name__c":"Ophthalmology","Tag_Category__c":"Specialist"},{"Tag_Name__c":"Inborn Errors of Metabolism","Tag_Category__c":"Cause;Disease Category","category_description":"Inherited metabolic diseases, or inborn errors of metabolism, are a group of genetic diseases that affect the ability of the body's cells to convert food into energy.","curated_tag_name":"Inherited metabolic diseases"},{"Tag_Name__c":"Mitochondrial","Tag_Category__c":"Account;Cause;Disease Category","category_description":"Mitochondrial diseases are a group of genetic diseases that affect the ability of the body's cells to make energy.","curated_tag_name":"Mitochondrial diseases"},{"Tag_Name__c":"Retinal","Tag_Category__c":"Account;Specialist","curated_tag_name":"Retinal disorders"},{"Tag_Name__c":"Peripheral Neuropathy","Tag_Category__c":"Account","curated_tag_name":"Peripheral neuropathy"},{"Tag_Name__c":"Epilepsy","Tag_Category__c":"Account;Specialist","curated_tag_name":"Epilepsy"},{"Tag_Name__c":"Neurodevelopmental disabilities","Tag_Category__c":"Specialist","curated_tag_name":"Neurodevelopmental disabilities"},{"Tag_Name__c":"Neuromuscular medicine","Tag_Category__c":"Specialist","curated_tag_name":"Neuromuscular medicine"},{"Tag_Name__c":"Pediatrics","Tag_Category__c":"Specialist"}],"Age_At_Onset__c":[{"Age_At_Onset__c":"Childhood","Provided_By__c":"ORPHA:644"}],"Diagnosis__c":[{"Type__c":"GTR","Curie__c":"MEDGEN:C1328349"}],"External_Identifier_Disease__c":[{"URL__c":"https://www.ncbi.nlm.nih.gov/books/NBK1224","Source__c":"Gene Review","Xref__c":"NBK1224"},{"URL__c":"https://www.ncbi.nlm.nih.gov/books/NBK1173","Source__c":"Gene Review","Xref__c":"NBK1173"},{"URL__c":"https://uts.nlm.nih.gov/uts/umls/concept/C1328349","Source__c":"C1328349","Xref__c":"C1328349"},{"URL__c":"https://www.ncbi.nlm.nih.gov/mesh/C537396","Source__c":"MONDO:0010794","Xref__c":"C537396"},{"URL__c":"https://www.orpha.net/en/disease/detail/644","Source__c":"C1328349; MONDO:0010794; ORPHA:644","Xref__c":"ORPHA:644"},{"URL__c":"https://www.omim.org/entry/551500","Source__c":"C1328349; MONDO:0010794; ORPHA:644","Xref__c":"OMIM:551500"},{"URL__c":"https://www.ebi.ac.uk/ols4/ontologies/doid/classes?obo_id=DOID%3A0111273","Source__c":"MONDO:0010794","Xref__c":"DOID:0111273"},{"URL__c":"https://www.ncbi.nlm.nih.gov/medgen/?term=231285","Source__c":"C1328349","Xref__c":"MEDGEN:231285"},{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=237984008","Source__c":"C1328349","Xref__c":"237984008"},{"URL__c":"https://medlineplus.gov/genetics/condition/neuropathy-ataxia-and-retinitis-pigmentosa","Source__c":"GARD:0000262","Xref__c":"https://medlineplus.gov/genetics/condition/neuropathy-ataxia-and-retinitis-pigmentosa"},{"URL__c":"http://purl.obolibrary.org/obo/MONDO_0010794","Source__c":"GARD:0000262","Xref__c":"MONDO:0010794"}],"GARD_Disease_Gene__c":[{"GeneSymbol__c":"MT-ATP6","GHR_URL__c":"https://medlineplus.gov/genetics/gene/mt-atp6","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true}],"Inheritance__c":["Mitochondrial inheritance"],"GARD_Disease_Feature__c":[{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Peripheral neuropathy affecting the sensory nerves.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000763","HPO_Synonym__c":"Damage to nerves that sense feeling; Peripheral sensory neuropathy","HPO_Name__c":"Sensory neuropathy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Sudden and involuntary contractions of one or more muscles.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003394","HPO_Synonym__c":"Muscle cramps; Muscle spasms","HPO_Name__c":"Muscle spasm","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002315","HPO_Synonym__c":"Headache; Headaches","HPO_Name__c":"Headache","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"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.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001250","HPO_Synonym__c":"Epileptic seizure; Seizures","HPO_Name__c":"Seizure","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A type of gait ataxia displaying progression of clinical severity.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007240","HPO_Synonym__c":"Gait ataxia, progressive","HPO_Name__c":"Progressive gait ataxia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Mottling (spots or blotches of different shades) of the retinal pigment epithelium, i.e., localized or generalized fundus pigment granularity associated with processes at the level of the retinal pigment epithelium.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007814","HPO_Synonym__c":"Focal hypopigmentation of the retinal pigment epithelium; Retinal pigment epithelium irregularity; RPE irregularity; RPE mottling; Salt and pepper retinal pigmentation; Salt and pepper retinopathy","HPO_Name__c":"Retinal pigment epithelial mottling","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Excluded (0%)","Feature__r":{"HPO_Description__c":"An abnormality of the mitochondria in muscle tissue.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0008316","HPO_Synonym__c":"Abnormal mitochondria in muscle","HPO_Name__c":"Abnormal mitochondria in muscle tissue","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007117","HPO_Name__c":"Corticospinal tract atrophy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000639","HPO_Synonym__c":"Involuntary, rapid, rhythmic eye movements","HPO_Name__c":"Nystagmus","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"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.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001263","HPO_Synonym__c":"Delayed cognitive development; Delayed development; Delayed developmental milestones; Delayed intellectual development; Delayed milestones; Delayed psychomotor development; Developmental delay; Developmental delay in early childhood; Developmental delay, global; Developmental retardation; GDD; Lack of psychomotor development; Motor and developmental delay; Motormental retardation; Psychomotor delay; Psychomotor development deficiency; Psychomotor development failure; Psychomotor developmental delay; Retarded development; Retarded mental development; Retarded psychomotor development","HPO_Name__c":"Global developmental delay","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"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).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001251","HPO_Synonym__c":"Cerebellar ataxia","HPO_Name__c":"Ataxia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A decreased magnitude of the sensory perception of sound.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000365","HPO_Synonym__c":"Deafness; Hearing defect; Hearing impairment; Hypacusis","HPO_Name__c":"Hearing impairment","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003739","HPO_Name__c":"Myoclonic spasms","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An inherited retinal disease subtype in which the rod photoreceptors appear to be more severely affected than the cone photoreceptors. Typical presentation is with nyctalopia (due to rod dysfunction) followed by loss of mid-peripheral field of vision, which gradually extends and leaves many patients with a small central island of vision due to the preservation of macular cones.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000510","HPO_Synonym__c":"Retinitis pigmentosa; Rod cone dystrophy","HPO_Name__c":"Rod-cone dystrophy","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A height below that which is expected according to age and sex norms. Although there is no universally accepted definition of short stature, many refer to \\\"short stature\\\" as height more than 2 standard deviations below the mean for age and sex (or below the 3rd percentile for age and sex dependent norms).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0004322","HPO_Synonym__c":"Decreased body height; Height less than 3rd percentile; Short stature; Small stature; Stature below 3rd percentile","HPO_Name__c":"Short stature","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An increase in size of the ventricular system of the brain.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002119","HPO_Synonym__c":"Cerebral ventricular dilatation; Dilated cerebral ventricle; Dilated cerebral ventricles; Dilated ventricles; Enlarged cerebral ventricles; Enlarged ventricles; Enlarged ventricular system; Large cerebral ventricles and cisternae; Ventricular dilatation","HPO_Name__c":"Ventriculomegaly","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A pale yellow discoloration of the optic disc (the area of the optic nerve head in the retina). The optic disc normally has a pinkish hue with a central yellowish depression.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000543","HPO_Synonym__c":"Pale optic disc","HPO_Name__c":"Optic disc pallor","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Severe intellectual disability (ID) is defined as a type of ID characterized by severely sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) the range of 20-34.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0010864","HPO_Synonym__c":"Early and severe mental retardation; Intellectual disability, severe; Mental retardation, severe; Severe mental retardation","HPO_Name__c":"Severe intellectual disability","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003487","HPO_Synonym__c":"Extensor plantar reflexes; Extensor plantar response; Extensor plantar responses; Positive Babinski sign","HPO_Name__c":"Babinski sign","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Atrophy of the cortex of the cerebrum.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002120","HPO_Synonym__c":"Cerebral cortex atrophy; Cortical atrophy; Decrease in size of the outer layer of the brain due to loss of brain cells","HPO_Name__c":"Cerebral cortical atrophy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A loss of global cognitive ability of sufficient amount to interfere with normal social or occupational function. Dementia represents a loss of previously present cognitive abilities, generally in adults, and can affect memory, thinking, language, judgment, and behavior.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000726","HPO_Synonym__c":"Dementia; Dementia, progressive; Progressive dementia","HPO_Name__c":"Dementia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"The presence of an increased number of twists and turns of the retinal arterioles.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001136","HPO_Synonym__c":"Tortuous retinal arterioles","HPO_Name__c":"Retinal arteriolar tortuosity","Feature_System__c":"Cardiovascular System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A lack of strength of the proximal muscles.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003701","HPO_Synonym__c":"Muscle weakness, proximal; Proximal limb muscle weakness; Proximal limb weakness; Weakness in muscles of upper arms and upper legs","HPO_Name__c":"Proximal muscle weakness","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Abnormal result of a test designed to test an individual's central and peripheral vision by determining the ability of the individual to perceive objects at differing locations of the visual field.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0030588","HPO_Name__c":"Abnormal visual field test","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An emotional state characterized by negative feelings of heightened frustration, annoyance, or feeling upset, often triggered by internal factors (e.g., fatigue, hunger, unfulfilled desires) or external factors (e.g., social or environmental challenges). Irritability may be unpredictable, and is accompanied by a lowered threshold for emotional reactivity and observable features (speech, facial expressions, or psychomotor activity).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000737","HPO_Synonym__c":"Cranky; Easily annoyed; Easily bothered; Easily upset; Grumpy; Hot-temper; Irritability; Irritable; Irritable mood; On edge; Quick-temper; Short fuse; Short tempered","HPO_Name__c":"Irritability","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A deviation from normal signal on magnetic resonance imaging (MRI) of the basal ganglia.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0012751","HPO_Name__c":"Abnormal basal ganglia MRI signal intensity","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Imaging_MRI"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"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.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000618","HPO_Synonym__c":"Blindness; Total vision loss","HPO_Name__c":"Blindness","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:644","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An absolute or relative decrease in retinal sensitivity extending from edge (periphery) of the visual field in a concentric pattern. The visual field is the area that is perceived simultaneously by a fixating eye.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001133","HPO_Synonym__c":"Concentric narrowing of visual field; Constricted visual field; Constricted visual fields; Limited peripheral vision; Reduced peripheral vision; Visual field constriction","HPO_Name__c":"Constriction of peripheral visual field","HPO_Feature_Type__c":"Symptom"}}],"tags":{"Cause":["Genetics","Inborn Errors of Metabolism","Mitochondrial"],"Disease Category":["Genetics","Neurology","Inborn Errors of Metabolism","Mitochondrial"],"Specialist":["Genetics","Neurology","Ophthalmology","Retinal","Epilepsy","Neurodevelopmental disabilities","Neuromuscular medicine","Pediatrics"],"Account":["Mitochondrial","Retinal","Peripheral Neuropathy","Epilepsy"]},"synonyms":["narp (neurogenic muscle weakness, ataxia, retinitis pigmentosa) syndrome"," neurogenic muscle weakness-ataxia-retinitis pigmentosa syndrome"," neurogenic muscle weakness, ataxia and retinitis pigmentosa"," neuropathy-ataxia-retinitis pigmentosa syndrome"]}