This report describes NESCAV syndrome (NESCAVS), a neurodegenerative disorder; this disease was previously named ‘intellectual disability, autosomal dominant 9’ (MRD9). The human gene implicated in NESCAVS is the kinesin gene KIF1A, which encodes an anterograde motor protein that transports membranous organelles and synaptic vesicle precursors along axonal microtubules. See the report for 'synaptic dysfunction, KIF1-related' (FBhh0000875) for information on experimental results using Drosophila models of this and related diseases.
[updated Oct. 2020 by FlyBase; FBrf0222196]
Intellectual disability is characterized by impairments in intellectual functioning and adaptive behavior; symptoms must be present before a child becomes 18 years old (http://medical-dictionary.thefreedictionary.com/mental+retardation; 2016.01.19).
Intellectual disability can be subdivided into syndromic forms, characterized by cognitive impairment accompanied by dysmorphic features, malformations or neurological abnormalities, and nonsyndromic forms, characterized by cognitive impairment without additional features (Basel-Vanagaite, 2008; DOI: 10.1002/9780470015902.a0021454).
[NESCAV SYNDROME; NESCAVS](https://omim.org/entry/614255)
[KINESIN FAMILY MEMBER 1A; KIF1A](https://omim.org/entry/601255)
NESCAV syndrome (NESCAVS) is a neurodegenerative disorder characterized by onset of features in infancy or early childhood. Affected individuals show global developmental delay with delayed walking or difficulty walking due to progressive spasticity mainly affecting the lower limbs and often leading to loss of independent ambulation. There is variably impaired intellectual development, speech delay, and learning disabilities and/or behavioral abnormalities. Additional features may include cortical visual impairment, often associated with optic atrophy, axonal peripheral neuropathy, seizures, dysautonomia, ataxia, and dystonia. Brain imaging often shows progressive cerebellar atrophy and thin corpus callosum. Some patients may show developmental regression, particularly of motor skills. The phenotype and presentation are highly variable (summary by Nemani et al., 2020; pubmed:32096284). [from MIM:614255; 2020.10.13]
NESCAV syndrome (NESCAVS) is caused by heterozygous mutation in the KIF1A gene. [from MIM:614255; 2020.10.13]
KIF1A encodes a member of the kinesin family; it functions as an anterograde motor protein that transports membranous organelles and synaptic vesicle precursors along axonal microtubules. [Gene Cards, KIF1A; 2018.08.22]
