- Scanning speech (HP:0002168): An abnormal pattern of speech in which the words are as if measured or scanned; there is a pause after every syllable, and the syllables themselves are pronounced slowly. Evidence: IEA. (OMIM:609055)
- Mutism (HP:0002300): Complete lack of speech or verbal communication in a person despite attempts to engage in conversation. Mutism as a phenomena assumes the individual has previous capacity for speech and in the pediatric population it assumes that the person is past the age of typical language development. Evidence: IEA. (OMIM:609055)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: IEA. (OMIM:609055)
- 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: IEA. (OMIM:609055)
- Dysarthria (HP:0001260): Dysarthric speech is a general description referring to a neurological speech disorder characterized by poor articulation. Depending on the involved neurological structures, dysarthria may be further classified as spastic, flaccid, ataxic, hyperkinetic and hypokinetic, or mixed. Evidence: IEA. (OMIM:609055)
- Rigidity (HP:0002063): Continuous involuntary sustained muscle contraction. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity. Evidence: IEA. (OMIM:609055)
- 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:609055)
- Psychomotor deterioration (HP:0002361): Loss of previously present mental and motor abilities. Evidence: IEA. (OMIM:609055)
- Progressive visual loss (HP:0000529): A reduction of previously attained ability to see. Evidence: IEA. (OMIM:609055)
- Death in childhood (HP:0003819): Death in during childhood, defined here as between the ages of 2 and 10 years. Evidence: IEA. (OMIM:609055)
- Vacuolated lymphocytes (HP:0001922): The presence of clear, sharply defined vacuoles in the lymphocyte cytoplasm. Evidence: IEA. (OMIM:609055)
- 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: IEA. (OMIM:609055)
- Optic atrophy (HP:0000648): Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy. Evidence: IEA. (OMIM:609055)
- Fingerprint intracellular accumulation of autofluorescent lipopigment storage material (HP:0003208): An intracellular accumulation of autofluorescent lipopigment storage material in a trabecular or fingerprint-like pattern. Evidence: IEA. (OMIM:609055)
- Loss of ambulation (HP:0002505): Inability to walk in a person who previous had the ability to walk. Evidence: IEA. (OMIM:609055)
- Rod-cone dystrophy (HP:0000510): 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. Evidence: IEA. (OMIM:609055)
- 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: IEA. (OMIM:609055)
- Decreased light- and dark-adapted electroretinogram amplitude (HP:0000654): Decreased amplitude of eletrical response upon electroretinography. Evidence: IEA. (OMIM:609055)
- Curvilinear intracellular accumulation of autofluorescent lipopigment storage material (HP:0003205): An intracellular accumulation of autofluorescent lipopigment storage material in a curved pattern. Evidence: IEA. (OMIM:609055)
These phenotypes are associated with the disease neuronal ceroid lipofuscinosis 9 (OMIM:609055).