Adult onset neurodegenerative disorder

STR: HTT_CAG

Green List (high evidence)

Triplet repeat length in HTT is measured within the NHS to diagnose Huntington's disease which is, typically, an adult-onset disorder leading to neurodegeneration. I think this is therefore a relevant genomic target for this panel and omission could pose clinical risk in terms of missed diagnoses.

Created: 25 Jan 2021, 4:26 p.m. | Last Modified: 25 Jan 2021, 4:26 p.m.

Panel Version: 2.38

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Huntington disease # 143100

Variants in this STR are reported as part of current diagnostic practice

Green List (high evidence)

STR repeat lengths have been reviewed and confirmed by the NHS Genomic Medicine Service.

Created: 15 Mar 2022, 4:02 p.m. | Last Modified: 15 Mar 2022, 4:02 p.m.

Panel Version: 2.267

After NHS Genomic Medicine Service consideration, this STR has been promoted back to green on the R58 panel.

Created: 8 Mar 2022, 3:24 p.m. | Last Modified: 8 Mar 2022, 3:24 p.m.

Panel Version: 2.260

Tagged 'for-review' to highlight the recent review by Helen Brittain (Genomics England Clinical Team) indicating that exclusion of this STR may increase risk of missed diagnoses. HTT_CAG was removed from this panel in October 2020 at request of the GMS Specialist Test Group.

Created: 26 Jan 2021, 11:11 a.m. | Last Modified: 26 Jan 2021, 11:11 a.m.

Panel Version: 2.38

Comment on list classification: This STR has been removed at the request of GHLs for the GMS Neurology Specialist Test Group as it is available as a core test for R68 Huntington Disease. Inclusion on panels for other neurological CIs raises concerns regarding counselling, and so it has been agreed that HTT_CAG will be excluded from this panel.

Created: 6 Oct 2020, 10:34 a.m. | Last Modified: 6 Oct 2020, 10:34 a.m.

Panel Version: 2.17

Green List (high evidence)

Green rating for STR submitted on behalf of Nick Beauchamp (Sheffield Diagnostic genetics Service), on behalf of Yorkshire and North East GLH for GMS Neurology specialist test group. Indicated that variants are reported as part of the current diagnostic practice.

Created: 23 Jul 2019, 4:58 p.m. | Last Modified: 23 Jul 2019, 4:58 p.m.

Panel Version: 1.75

Green rating for STR submitted on behalf of James Polke (North Bristol NHS Trust), also indicated that variants are reported as part of the current diagnostic practice, on behalf of London North GLH for GMS Neurology specialist test group.

Created: 24 Apr 2019, 2:35 p.m.

Source PanelApp panels : Hereditary spastic paraplegia v1.143, Parkinson Disease and Complex Parkinsonism v1.64, Early onset dementia (encompassing fronto-temporal dementia and prion disease) v1.46, Hereditary ataxia v1.150
Sources: Expert list

Created: 21 Dec 2018, 9:07 a.m.

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Huntington disease 143100

Variants in this STR are reported as part of current diagnostic practice