- Atypical behavior (HP:0000708): Atypical behavior is an abnormality in a person's actions that can be controlled or modulated by the will of the individual. While abnormal behaviors can be difficult to control, they are distinct from other abnormal actions that cannot be affected by the individual's will. Evidence: PCS. (PMID:27080313)
- Middle age onset (HP:0003596): A type of adult onset with onset of symptoms at the age of 40 to 60 years. Evidence: PCS. Frequency: 16/19. (PMID:27080313)
- Frontotemporal dementia (HP:0002145): A dementia associated with degeneration of the frontotemporal lobe and clinically associated with personality and behavioral changes such as disinhibition, apathy, and lack of insight. The hallmark feature of frontotemporal dementia is the presentation with focal syndromes such as progressive language dysfunction, or aphasia, or behavioral changes characteristic of frontal lobe disorders. Evidence: PCS. Frequency: 2/13. (PMID:27080313)
- 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: PCS. (PMID:27080313)
- Late onset (HP:0003584): A type of adult onset with onset of symptoms after the age of 60 years. Evidence: PCS. Frequency: 3/9. (PMID:27080313)
- Amyotrophic lateral sclerosis (HP:0007354). Evidence: PCS. Frequency: 9/13. (PMID:27080313)
- Fasciculations (HP:0002380): Fasciculations are observed as small, local, involuntary muscle contractions (twitching) visible under the skin. Fasciculations result from increased irritability of an axon (which in turn is often a manifestation of disease of a motor neuron). This leads to sporadic discharges of all the muscle fibers controlled by the axon in isolation from other motor units. Evidence: PCS. (PMID:27080313)
- Limb muscle weakness (HP:0003690): Reduced strength and weakness of the muscles of the arms and legs. Evidence: PCS. (PMID:27080313)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: PCS. (PMID:27080313)
- 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:27080313)
- Muscle fibrillation (HP:0010546): Fine, rapid twitching of individual muscle fibers with little or no movement of the muscle as a whole as ascertained by electromyography (EMG). If a motor neuron or its axon is destroyed, the muscle fibers it innervates undergo denervation atrophy. This leads to hypersensitivity of individual muscle fibers to acetyl choline so that they may contract spontaneously. Isolated activity of individual muscle fibers is generally so fine it cannot be seen through the intact skin, although it can be recorded as a short-duration spike in the EMG. Evidence: PCS. (PMID:27080313)
These phenotypes are associated with the disease frontotemporal dementia and/or amyotrophic lateral sclerosis 5 (OMIM:619141).