rs1555509538
Variant summary
Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong
The NM_000548.5(TSC2):āc.2966G>Cā(p.Ser989Thr) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,158 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (ā ā ). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S989G) has been classified as Uncertain significance.
Frequency
Consequence
NM_000548.5 missense, splice_region
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_pathogenic. Variant got 6 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | UniProt |
---|---|---|---|---|---|---|---|
TSC2 | NM_000548.5 | c.2966G>C | p.Ser989Thr | missense_variant, splice_region_variant | 26/42 | ENST00000219476.9 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|
TSC2 | ENST00000219476.9 | c.2966G>C | p.Ser989Thr | missense_variant, splice_region_variant | 26/42 | 5 | NM_000548.5 |
Frequencies
GnomAD3 genomes Cov.: 33
GnomAD4 exome AF: 6.85e-7 AC: 1AN: 1460158Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1AN XY: 726408
GnomAD4 genome Cov.: 33
ClinVar
Submissions by phenotype
Tuberous sclerosis 2 Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Invitae | Aug 24, 2020 | Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with TSC2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with threonine at codon 989 of the TSC2 protein (p.Ser989Thr). The serine residue is moderately conserved and there is a small physicochemical difference between serine and threonine. This variant also falls at the last nucleotide of exon 26 of the TSC2 coding sequence, which is part of the consensus splice site for this exon. Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. - |
Hereditary cancer-predisposing syndrome Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Ambry Genetics | Oct 12, 2023 | The c.2966G>C variant (also known as p.S989T), located in coding exon 25 of the TSC2 gene, results from a G to C substitution at nucleotide position 2966. The amino acid change results in serine to threonine at codon 989, an amino acid with similar properties. However, this change occurs in the last base pair of coding exon 25, which makes it likely to have some effect on normal mRNA splicing. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site; however direct evidence is insufficient. In addition, this variant occurs in an exon that is absent in biologically relevant transcripts (Ekong R et al. Hum. Mutat., 2016 Apr;37:364-70); therefore the clinical impact is uncertain. As a missense substitution, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. - |
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at