Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong
The NM_000548.5(TSC2):c.2220+4C>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).
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]
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Jul 12, 2021
The c.2220+4C>A intronic variant results from a C to A substitution 4 nucleotides after coding exon 19 in the TSC2 gene. This nucleotide position is not conserved on limited sequence alignment. In silico splice site analysis predicts that this alteration may result in the creation or strengthening of a novel splice acceptor site. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -