Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_Strong
The NM_000548.5(TSC2):c.1229T>C(p.Leu410Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L410R) has been classified 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 Pathogenic. Variant got 10 ACMG points.
PM1
?
PM1 - Located in a mutational hot spot and/or critical and well-established functional domain (e.g., active site of an enzyme) without benign variation
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 5 benign, 14 uncertain in NM_000548.5
PM2
?
PM2 - Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium
Very rare variant in population databases, with high coverage;
PM5
?
PM5 - Novel missense change at an amino acid residue where a different missense change determined to be pathogenic has been seen before
Other missense variant is known to change same aminoacid residue: Variant chr16-2061980-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 49680.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=2, not_provided=1, Likely_pathogenic=2}.
PP3
?
PP3 - Multiple lines of computational evidence support a deleterious effect on the gene or gene product (conservation, evolutionary, splicing impact, etc.)
MetaRNN computational evidence supports a deleterious effect, 0.964
Uncertain significance, criteria provided, single submitter
clinical testing
GeneDx
May 16, 2019
Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -
Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);.;Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);.;Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);Loss of helix (P = 3e-04);.;