This report describes ataxia-oculomotor apraxia 1, an early-onset autosomal recessive cerebellar ataxia with peripheral axonal neuropathy, oculomotor apraxia, and hypoalbuminemia. The human gene implicated is APTX, which encodes aprataxin, a member of the histidine triad (HIT) superfamily. There is one moderate-scoring fly ortholog, Dmel\Aptx, for which multiple genetic reagents, including classical alleles, RNAi-targeting constructs, and alleles caused by insertional mutagenesis have been generated.
Human APTX has not been introduced into flies.
Mushroom body-specific RNAi knockdown of Dmel\Aptx significantly affected startle and spontaneous induced walking behavio, but does not result in an increase in apoptosis in Kenyon cells.
[updated June 2024 by FlyBase; FBrf0222196]
Autosomal recessive cerebellar ataxias (ARCA) are a heterogeneous group of rare neurological disorders involving both central and peripheral nervous system, and in some case other systems and organs, and characterized by degeneration or abnormal development of cerebellum and spinal cord, autosomal recessive inheritance and, in most cases, early onset occurring before the age of 20 years (Palau and Espinos, 2006; pubmed:17112370).
The hereditary ataxias are a group of genetic disorders characterized by slowly progressive incoordination of gait and often associated with poor coordination of hands, speech, and eye movements. Frequently, atrophy of the cerebellum occurs. [from Gene Reviews, Hereditary Ataxia Overview; pubmed:20301317; 2017.06.16]
See also Jayadev and Bird, 2013 (pubmed:23538602).
Autosomal recessive spinocerebellar ataxia is a neurologic disorder characterized by onset of progressive gait difficulties, eye movement abnormalities, and dysarthria in the first or second decade of life (summary, Dy et al, 2105; pubmed:26224725). [from MIM:609270; 2020.07.13]
[ATAXIA, EARLY-ONSET, WITH OCULOMOTOR APRAXIA AND HYPOALBUMINEMIA; EAOH](https://omim.org/entry/208920)
[APRATAXIN; APTX](https://omim.org/entry/606350)
Ataxia-oculomotor apraxia syndrome is an early-onset autosomal recessive cerebellar ataxia with peripheral axonal neuropathy, oculomotor apraxia (defined as the limitation of ocular movements on command), and hypoalbuminemia (Moreira et al., 2001, pubmed:11170899) [from MIM:208920; 2024.06.11]
Early-onset ataxia with oculomotor apraxia and hypoalbuminemia (EAOH) is caused by homozygous or compound heterozygous mutation in the gene encoding aprataxin (APTX) on chromosome 9p21. Adult-onset ataxia with oculomotor apraxia is also caused by mutation in the APTX gene. [from MIM:208920; 2024.06.11]
The APTX gene encodes aprataxin, a member of the histidine triad (HIT) superfamily, members of which have nucleotide-binding and diadenosine polyphosphate hydrolase activities (Date et al., 2001, pubmed:11586299). [from MIM:606350; 2024.06.11]
One to one (1 human to 1 Drosophila); APTX has one moderate-scoring Drosophila ortholog, Aptx.
Moderate scoring ortholog of human APTX (1 Drosophila to 2 human).