Adult onset neurodegenerative disorder

Gene: CLCN2

The mode of inheritance of this gene has been updated to 'BIALLELIC, autosomal or pseudoautosomal' following NHS Genomic Medicine Service approval.

Created: 1 Feb 2023, 12:22 p.m. | Last Modified: 1 Feb 2023, 12:22 p.m.

Panel Version: 3.49

Comment on mode of inheritance: MOI should be changed from 'Both mono- and biallelic' to 'Biallelic' only. Features of neurodegeneration are seen in CLCN2-related Leukoencephalopathy (MIM# 615651) which is caused by biallelic variants. Autosomal dominant pathogenic variants are associated with hyperaldosteronism (MIM# 605635) and susceptibility to idiopathic epilepsy (MIM# 607628) but neither of these phenotypes are relevant to this panel.

Created: 15 Oct 2021, 1:42 p.m. | Last Modified: 15 Oct 2021, 1:42 p.m.

Panel Version: 2.200

Green List (high evidence)

Leukoencephalopathy with ataxia is an autosomal recessive neurologic disorder with a characteristic pattern of white matter abnormalities on brain MRI. Affected individuals have prominent signal abnormalities and decreased apparent diffusion coefficient (ADC) values in the posterior limbs of the internal capsules, middle cerebral peduncles, pyramidal tracts in the pons, and middle cerebellar peduncles. The findings suggest myelin microvacuolation restricted to certain brain regions. Clinical features include ataxia and unstable gait; more variable abnormalities may include visual field defects, headaches, and learning disabilities, can be adult or childhood onset. >3 cases

Created: 2 Sep 2019, 4:06 p.m. | Last Modified: 2 Sep 2019, 4:06 p.m.

Panel Version: 1.99

Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal

Phenotypes
{Epilepsy, juvenile absence, susceptibility to, 2}, 607628; {Epilepsy, idiopathic generalized, susceptibility to, 11}, 607628; {Epilepsy, juvenile myoclonic, susceptibility to, 8}, 607628; Leukoencephalopathy with ataxia, 615651

Green List (high evidence)

Two peaks of onset, childhood and adult

Created: 23 Jul 2019, 3:35 p.m. | Last Modified: 23 Jul 2019, 3:35 p.m.

Panel Version: 1.72

Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal

Publications

• 23707145

I don't know

Review and rating from Tracy Lester (Oxford Medical Genetics Laboratories Oxford University Hospitals NHS Foundation Trust) on behalf of Wessex and West Midlands GLH for GMS Neurology specialist test group. All the green and amber, except for the genes with triplet repeats, were reviewed.

Created: 2 Sep 2019, 4:46 p.m. | Last Modified: 2 Sep 2019, 4:46 p.m.

Panel Version: 1.101

Review and rating submitted by Nick Beauchamp (Sheffield Diagnostic genetics Service), on behalf of Yorkshire and North East GLH for GMS Neurology specialist test group.

Created: 23 Jul 2019, 3:51 p.m. | Last Modified: 23 Jul 2019, 3:51 p.m.

Panel Version: 1.74

Review and rating submitted byJames Polke (North Bristol NHS Trust), unless specified in the review comment, on behalf of London North GLH for GMS Neurology specialist test group.

Created: 23 Apr 2019, 5:35 p.m.

Green List (high evidence)