Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_ModeratePM2PP5_Moderate
The NM_000548.5(TSC2):c.3611-2A>G variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).
TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]
Verdict is Likely_pathogenic. Variant got 6 ACMG points.
PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.03761062 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 16-2081593-A-G is Pathogenic according to our data. Variant chr16-2081593-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 238023.Status of the report is criteria_provided_single_submitter, 1 stars.
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This sequence change affects an acceptor splice site in intron 30 of the TSC2 gene. It is expected to disrupt mRNA splicing and likely results in an absent or disrupted protein product. This variant has not been reported in the literature in an individual with a TSC2-related disease. In summary, donor and acceptor splice site variants are typically truncating (PMID: 16199547), and truncating variants in TSC2 are known to be pathogenic (PMID: 10205261, 17304050). However, without additional functional and/or genetic data, this variant has been classified as Likely Pathogenic. -