9-21971015-A-T
Variant summary
Our verdict is Likely benign. Variant got -1 ACMG points: 4P and 5B. PM1PP3_ModerateBS1_SupportingBS2
The NM_000077.5(CDKN2A):c.344T>A(p.Val115Glu) variant causes a missense change. The variant allele was found at a frequency of 0.00000622 in 1,607,670 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).
Frequency
Consequence
NM_000077.5 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -1 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
CDKN2A | ENST00000304494.10 | c.344T>A | p.Val115Glu | missense_variant | Exon 2 of 3 | 1 | NM_000077.5 | ENSP00000307101.5 | ||
CDKN2A | ENST00000579755.2 | c.387T>A | p.Arg129Arg | synonymous_variant | Exon 2 of 3 | 1 | NM_058195.4 | ENSP00000462950.1 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152208Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000209 AC: 5AN: 239434Hom.: 0 AF XY: 0.0000153 AC XY: 2AN XY: 131022
GnomAD4 exome AF: 0.00000618 AC: 9AN: 1455462Hom.: 0 Cov.: 31 AF XY: 0.00000552 AC XY: 4AN XY: 724334
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152208Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1AN XY: 74368
ClinVar
Submissions by phenotype
not provided Uncertain:2
This variant is denoted CDKN2A c.344T>A at the cDNA level, p.Val115Glu (V115E) at the protein level, and results in the change of a Valine to a Glutamic Acid (GTG>GAG). This variant was observed in a patient with oral squamous cell carcinoma and in a patient with non-small cell lung cancer (Tengs 2006, Lim 2014). CDKN2A Val115Glu was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, suggesting it is not a common benign variant in these populations. Since Valine and Glutamic Acid differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. CDKN2A Val115Glu occurs at a position where amino acids with properties similar to Valine are tolerated across species and is located in the ANK4 Repeat domain (UniProt). In silico analyses predict that this variant is probably damaging to protein structure and function. Based on currently available evidence, it is unclear whether CDKN2A Val115Glu is a pathogenic or benign variant. We consider it to be a variant of uncertain significance. -
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Hereditary cancer-predisposing syndrome Uncertain:2
The CDKN2A locus encodes two different gene products, p16INK4a and p14ARF (https://www.ncbi.nlm.nih.gov/books/NBK7030/). This missense variant replaces valine with glutamic acid at codon 115 of the CDKN2A (p16INK4A) protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with non-small cell lung cancer and oral tongue squamous cell carcinoma (PMID: 16171945, 24436120). This variant has been identified in 6/270818 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
The p.V115E variant (also known as c.344T>A), located in coding exon 2 of the CDKN2A gene, results from a T to A substitution at nucleotide position 344. The valine at codon 115 is replaced by glutamic acid, an amino acid with dissimilar properties. This alteration has been reported in both the tumor and normal tissue of an individual with an oral/tongue squamous cell carcinoma at age 42, who had no previous history of cancer and no family history of cancer (Lim AM et al. Int. J. Cancer 2014 Aug; 135(4):887-95). This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Melanoma and neural system tumor syndrome Uncertain:1
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Melanoma and neural system tumor syndrome;C1835044:Melanoma, cutaneous malignant, susceptibility to, 2;C1838547:Melanoma-pancreatic cancer syndrome Uncertain:1
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Familial melanoma Uncertain:1
This sequence change replaces valine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 115 of the CDKN2A (p16INK4a) protein (p.Val115Glu). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with oral tongue squamous cell carcinomas (PMID: 24436120). ClinVar contains an entry for this variant (Variation ID: 246437). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Experimental studies have shown that this missense change affects CDKN2A (p16INK4a) function (PMID: 8573142). 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. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at