Phenotypes associated with the disease mitochondrial complex I deficiency, nuclear type 2 (OMIM:618222, an entry in Online Mendelian Inheritance in Man):
- Dystonia (HP:0001332, a Human Phenotype Ontology term): An abnormally increased muscular tone that causes fixed abnormal postures. There is a slow, intermittent twisting motion that leads to exaggerated turning and posture of the extremities and trunk. Evidence: PCS. Frequency: 1/1. (PMID:15159508)
- Seizure (HP:0001250, a Human Phenotype Ontology term): 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:618222)
- Hypotonia (HP:0001252, a Human Phenotype Ontology term): 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: 1/1. (PMID:9837812)
- Vertical nystagmus (HP:0010544, a Human Phenotype Ontology term): Vertical nystagmus may present with either up-beating or down-beating eye movements or both. When present in the straight-ahead position of gaze it is referred to as upbeat nystagmus or downbeat nystagmus. Evidence: PCS. Frequency: 1/1. (PMID:15159508)
- Nystagmus (HP:0000639, a Human Phenotype Ontology term): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: IEA. (OMIM:618222)
- Apneic episodes in infancy (HP:0005949, a Human Phenotype Ontology term): Recurrent episodes of apnea occurring during infancy. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Ventriculomegaly (HP:0002119, a Human Phenotype Ontology term): An increase in size of the ventricular system of the brain. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Brisk reflexes (HP:0001348, a Human Phenotype Ontology term): Tendon reflexes that are noticeably more active than usual (conventionally denoted 3+ on clinical examination). Brisk reflexes may or may not indicate a neurological lesion. They are distinguished from hyperreflexia by the fact that hyerreflexia is characterized by hyperactive repeating (clonic) reflexes, which are considered to be always abnormal. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Hyperreflexia (HP:0001347, a Human Phenotype Ontology term): Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles. Evidence: IEA. (OMIM:618222)
- Neonatal onset (HP:0003623, a Human Phenotype Ontology term): Onset of signs or symptoms of disease within the first 28 days of life. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Primitive reflex (HP:0002476, a Human Phenotype Ontology term): The primitive reflexes are a group of behavioral motor responses which are found in normal early development, are subsequently inhibited, but may be released from inhibition by cerebral, usually frontal, damage. They are thus part of a broader group of reflexes which reflect release phenomena, such as exaggerated stretch reflexes and extensor plantars. They do however involve more complex motor responses than such simple stretch reflexes, and are often a normal feature in the neonate or infant. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Juvenile onset (HP:0003621, a Human Phenotype Ontology term): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 1/1. (PMID:15159508)
- Gait disturbance (HP:0001288, a Human Phenotype Ontology term): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: IEA. (OMIM:618222)
- Increased circulating pyruvate concentration (HP:0003542, a Human Phenotype Ontology term): The concentration of pyruvate in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Feeding difficulties (HP:0011968, a Human Phenotype Ontology term): Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Dysarthria (HP:0001260, a Human Phenotype Ontology term): 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: PCS. Frequency: 1/1. (PMID:15159508)
- Poor suck (HP:0002033, a Human Phenotype Ontology term): An inadequate sucking reflex, resulting in the difficult of newborns to be breast-fed. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Global developmental delay (HP:0001263, a Human Phenotype Ontology term): 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: IEA. Frequency: Very rare (HP:0040284, a Human Phenotype Ontology term). (OMIM:618222)
- Increased circulating lactate concentration (HP:0002151, a Human Phenotype Ontology term): Abnormally increased level of blood lactate (2-hydroxypropanoic acid). Lactate is produced from pyruvate by lactate dehydrogenase during normal metabolism. The terms lactate and lactic acid are often used interchangeably but lactate (the component measured in blood) is strictly a weak base whereas lactic acid is the corresponding acid. Lactic acidosis is often used clinically to describe elevated lactate but should be reserved for cases where there is a corresponding acidosis (pH below 7.35). Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Gliosis (HP:0002171, a Human Phenotype Ontology term): Gliosis is the focal proliferation of glial cells in the central nervous system. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Hypercapnia (HP:0012416, a Human Phenotype Ontology term): Abnormally elevated blood carbon dioxide (CO2) level. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Respiratory insufficiency (HP:0002093, a Human Phenotype Ontology term). Evidence: IEA. (OMIM:618222)
- Decreased activity of mitochondrial complex I (HP:0011923, a Human Phenotype Ontology term): A reduction in the activity of the mitochondrial respiratory chain complex I, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 1/1. (PMID:15159508)
- Ankle clonus (HP:0011448, a Human Phenotype Ontology term): Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Ankle clonus is tested by rapidly flexing the foot upward. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Dyskinesia (HP:0100660, a Human Phenotype Ontology term): A movement disorder which consists of effects including diminished voluntary movements and the presence of involuntary movements. Evidence: IEA. (OMIM:618222)
- Hypertrophic cardiomyopathy (HP:0001639, a Human Phenotype Ontology term): Hypertrophic cardiomyopathy (HCM) is defined by the presence of increased ventricular wall thickness or mass in the absence of loading conditions (hypertension, valve disease) sufficient to cause the observed abnormality. Evidence: IEA. (OMIM:618222)
- Autosomal recessive inheritance (HP:0000007, a Human Phenotype Ontology term): 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:9837812)
- Drowsiness (HP:0002329, a Human Phenotype Ontology term): Abnormal feeling of sleepiness or difficulty staying awake. Evidence: PCS. Frequency: 1/1. (PMID:9837812)
- Falls (HP:0002527, a Human Phenotype Ontology term). Evidence: PCS. Frequency: 1/1. (PMID:15159508)
- Apnea (HP:0002104, a Human Phenotype Ontology term): Lack of breathing with no movement of the respiratory muscles and no exchange of air in the lungs. This term refers to a disposition to have recurrent episodes of apnea rather than to a single event. Evidence: IEA. (OMIM:618222)
- Weak cry (HP:0001612, a Human Phenotype Ontology term). Evidence: PCS. Frequency: 1/1. (PMID:9837812)