Our verdict is Likely pathogenic. Variant got 6 ACMG points: 7P and 1B. PM1PM2PP2PP3_ModerateBP6
The NM_000368.5(TSC1):c.110G>C(p.Arg37Pro) 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 Lovd as Likely benign (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R37H) has been classified as Likely benign.
TSC1 (HGNC:12362): (TSC complex subunit 1) This gene is a tumor suppressor gene that encodes the growth inhibitory protein hamartin. The encoded protein interacts with and stabilizes the GTPase activating protein tuberin. This hamartin-tuberin complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. This protein also functions as a co-chaperone for Hsp90 that inhibits its ATPase activity. This protein functions as a facilitator of Hsp90-mediated folding of kinase and non-kinase clients, including TSC2 and thereby preventing their ubiquitination and proteasomal degradation. 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.
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 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 10 uncertain in NM_000368.5
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;
PP2
?
PP2 - Missense variant in a gene that has a low rate of benign missense variation and in which missense variants are a common mechanism of disease
Missense variant where missense usually causes diseases, TSC1
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, 0.92
BP6
?
BP6 - Reputable source recently reports variant as benign, but the evidence is not available to the laboratory to perform an independent evaluation
Variant 9-132927301-C-G is Benign according to our data. Variant chr9-132927301-C-G is described in Lovd as [Likely_benign].