Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PP3_StrongPP5_Moderate
The NM_000548.5(TSC2):c.4790T>C(p.Leu1597Pro) variant causes a missense change. 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 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
In a domain Rap-GAP (size 227) in uniprot entity TSC2_HUMAN there are 284 pathogenic changes around while only 47 benign (86%) in NM_000548.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.993
PP5
Variant 16-2086320-T-C is Pathogenic according to our data. Variant chr16-2086320-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 49320.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr16-2086320-T-C is described in Lovd as [Pathogenic]. Variant chr16-2086320-T-C is described in Lovd as [Pathogenic].
Review Status: criteria provided, single submitter
Collection Method: clinical testing
This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 1597 of the TSC2 protein (p.Leu1597Pro). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with tuberous sclerosis (PMID: 11112665). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 49320). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt TSC2 protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -