Optic neuropathy

Gene: SLC25A46

Green List (high evidence)

SLC25A46 (solute carrier family 25 member 46)
EnsemblGeneIds (GRCh38): ENSG00000164209
EnsemblGeneIds (GRCh37): ENSG00000164209
OMIM: 610826, Gene2Phenotype
SLC25A46 is in 17 panels

3 reviews

Achchuthan Shanmugasundram (Genomics England Curator)

Green List (high evidence)

Comment on classification of this gene: The rating for this gene should be GREEN, as this gene has been implicated in optic atrophy, as identified from biallelic loss-of-function variants from at least 10 unrelated individuals/ families from multiple ethnicities and supported by results from animal models.

Two brothers of consanguineous parents of Pakistani origin were identified with homozygous variant in SLC25A46 (c.413T>G./ p.Leu138Arg). The younger of the two brothers was presented with balancing difficulties in infancy, prominent myoclonus, cerebellar ataxia, profound visual loss, rod cone dysfunction, exotropia, difficulty initiating saccades, mild spasticity, and axonal sensory-motor neuropathy leading to trophic changes (PMID:27430653). Optic atrophy was also reported in all four families identified with either compound heterozygous or homozygous variants (c.165_166insC/ p.His56fs*94 & c.746G>A/ p.Gly249Asp, c.1018C>T/ p.Arg340Cys, c.1005A>T/ p.Glu335Asp and c.882_885dupTTAC/ p.Asn296fs*297 & c.998C>T/ p.Pro333Leu) from Abrams et al, 2015 (PMID:26168012).

Another homozygous variant (c.775C>T/ p.Arg259Cys) was found in a 28-year old Saudi patient, her sister and her four cousins and the patient was presented with optic atrophy and progressive weakness. Her sister had optic atrophy with minimal limb spasticity, while her four first cousins had impaired vision and difficulty or inability to walk. None of them had cerebellar atrophy or axonal neuropathy (PMID:28369803).

A study on patients from three North African families (Two siblings from Tunisian family and two unrelated Algerians) showed that the previously reported variant p.Arg340Cys (displayed in Tunisian siblings and one Algerian patient) was associated with childhood onset, optic atrophy, gait and speech difficulties and wasting of the lower limbs, and the Algerian patient with the novel variant p.Trp160Ser did not present with optic atrophy (PMID:28558379).

A six year old boy with homozygous missense variant c.770G>A (p.Arg257Gln) was reported with optic atrophy, peripheral neuropathy, ataxia, but not cerebellar atrophy (PMID:30178502). p.Arg340Cys variant was also identified in an eleven year old male patient and other unaffected family members in another study and the patient was presented with insidious onset, progressive vision loss and swaying since 8  years of age. The other presentations were gait ataxia, torticollis to left and tilt to right, head tremors and myoclonus (PMID:33816684).

Mouse models with loss-of-function mutation or lacking SLC25A46 gene manifest the main clinical features identified in patients such as ataxia, optic atrophy, cerebellar hypoplasia and peripheral neuropathy which were completely rescued by expression of human ortholog (PMID:28376086; PMID:28934388). The results suggest that the gene loss causes degeneration in neurons by affecting mitochondrial dynamics and energy production.

SLC25A46 has been associated with neuropathy, hereditary motor and sensory, type VIB in OMIM and Gene2Phenotype and with pontocerebellar hypoplasia, type 1E in OMIM.
Created: 11 Dec 2022, 10 a.m. | Last Modified: 11 Dec 2022, 10 a.m.
Panel Version: 3.1

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Optic atrophy, MONDO:0003608; Neuropathy, hereditary motor and sensory, type VIB, MIM# 616505; Pontocerebellar hypoplasia, type 1E, MIM# 619303, MONDO:0030260

Publications

Tom Cullup (Great Ormond Street Hospital)

Green List (high evidence)

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Neuropathy, hereditary motor and sensory, type VIB, 616505

Publications

Sarah Leigh (Genomics England Curator)

Green List (high evidence)

Associated with phenotype (optic atrophy) in OMIM, not in G2P. At least 10 variants reported
Created: 12 Sep 2017, 3:03 p.m.

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Neuropathy, hereditary motor and sensory, type VIB 616505

Publications

History Filter Activity

11 Dec 2022, Gel status: 3

Set Phenotypes

Achchuthan Shanmugasundram (Genomics England Curator)

Phenotypes for gene: SLC25A46 were changed from Neuropathy, hereditary motor and sensory, type VIB 616505 to Optic atrophy, MONDO:0003608; Neuropathy, hereditary motor and sensory, type VIB, MIM# 616505; Pontocerebellar hypoplasia, type 1E, MIM# 619303, MONDO:0030260

11 Dec 2022, Gel status: 3

Set publications

Achchuthan Shanmugasundram (Genomics England Curator)

Publications for gene: SLC25A46 were set to 26168012; 28369803

19 Mar 2019, Gel status: 3

Added New Source, Status Update

Ivone Leong (Genomics England Curator)

Source London North GLH was added to SLC25A46. Rating Changed from Green List (high evidence) to Green List (high evidence)

12 Sep 2017, Gel status: 4

Set publications

Sarah Leigh (Genomics England Curator)

Publications for SLC25A46 were set to 26168012; 28369803

12 Sep 2017, Gel status: 4

Gene classified by Genomics England curator

Sarah Leigh (Genomics England Curator)

This gene has been classified as Green List (High Evidence).

12 Sep 2017, Gel status: 0

Created

Sarah Leigh (Genomics England Curator)

SLC25A46 was created by sleigh

12 Sep 2017, Gel status: 0

Added New Source

Sarah Leigh (Genomics England Curator)

SLC25A46 was added to Inherited optic neuropathiespanel. Sources: Literature