Mosaic skin disorders - deep sequencing
Gene: TEKComment on list classification: Multiple cases of sporadic vascular malformations due to cutaneous mosaicism of a TEK variant (PMID: 19079259; 30677207; 34850385; 35460567; 35740480; 36924216). Different variants reported but the L914F substitution is most common and as are double variants found in cis. Somatic variants may not be picked up via other panels for the phenotype (R326) and therefore this gene should be promoted to Green at then next GMS panel update.Created: 23 Aug 2023, 10:56 a.m. | Last Modified: 23 Aug 2023, 10:56 a.m.
Panel Version: 2.27
Multiple cutaneous and mucosal venous malformations (VMCM) and blue rubber bleb naevus (BRBN) usually caused by double variants in cis; commonly Y897C-R915C in VMCM and T1105N-T1106P in BRBN. Unifocal venous malformation association with single somatic hit, most commonly L914F.Created: 5 May 2023, 2:19 p.m. | Last Modified: 5 May 2023, 2:19 p.m.
Panel Version: 2.1
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Blue rubber bleb naevus; multiple cutaneous and mucosal venous malformations (VMCM)
Publications
Mode of pathogenicity
Loss-of-function variants (as defined in pop up message) DO NOT cause this phenotype - please provide details in the comments
As advised by Genomics England clinician - "TEK is currently green on vascular and DDG2P panels, activating germline mutations cause cutaneous mucosal venous malformations, somatic mutations cause blue rubber bleb naevus syndrome. I don’t know how much evidence there is for blood mosaicism detection (versus tissue testing). Soblet et al, 2017, (PMID 27519652), didn’t find the pathogenic variants (identified through tissue testing) with targeted deep sequencing in blue rubber bleb naevus syndrome, but did find one at the 1-5% level in sporadic multifocal vascular malformation (probably all related conditions??). As not much targeted deep sequencing has been done it’s possible this would be a good future one.
Sources: Expert ReviewCreated: 12 Dec 2019, 5:14 p.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
Venous malformations, multiple cutaneous and mucosal, 600195
Publications
Phenotypes for gene: TEK were changed from Venous malformations, multiple cutaneous and mucosal, 600195 to Venous malformations, multiple cutaneous and mucosal, OMIM:600195; Unifocal and multifocal sporadic venous malformations; Blue rubber bleb naevus
Publications for gene: TEK were set to 27519652
Mode of pathogenicity for gene: TEK was changed from None to Loss-of-function variants (as defined in pop up message) DO NOT cause this phenotype - please provide details in the comments
Tag somatic tag was added to gene: TEK. Tag Q3_23_promote_green tag was added to gene: TEK. Tag Q3_23_NHS_review tag was added to gene: TEK.
Gene: tek has been classified as Amber List (Moderate Evidence).
Gene: tek has been classified as Amber List (Moderate Evidence).
gene: TEK was added gene: TEK was added to Mosaic skin disorders - deep sequencing. Sources: Expert Review Mode of inheritance for gene: TEK was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown Publications for gene: TEK were set to 27519652 Phenotypes for gene: TEK were set to Venous malformations, multiple cutaneous and mucosal, 600195 Review for gene: TEK was set to AMBER