9-21970944-C-T
Variant summary
Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate
The NM_000077.5(CDKN2A):c.415G>A(p.Gly139Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,460,010 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign 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. G139R) has been classified as Uncertain significance.
Frequency
Consequence
NM_000077.5 missense
Scores
Clinical Significance
Conservation
Publications
- melanoma, cutaneous malignant, susceptibility to, 2Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
- melanoma-pancreatic cancer syndromeInheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics
- familial atypical multiple mole melanoma syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- melanoma and neural system tumor syndromeInheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
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ACMG classification
Our verdict: Uncertain_significance. The variant received 0 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD2 exomes AF: 0.00 AC: 0AN: 246404 AF XY: 0.00
GnomAD4 exome AF: 0.00000274 AC: 4AN: 1460010Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3AN XY: 726382 show subpopulations
Age Distribution
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
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 glycine with serine at codon 139 of the CDKN2A (p16INK4A) protein. Computational prediction suggests that this variant may not impact protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with breast cancer (PMID: 32957588). This variant has not been identified 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.G139S variant (also known as c.415G>A), located in coding exon 2 of the CDKN2A gene, results from a G to A substitution at nucleotide position 415. The glycine at codon 139 is replaced by serine, an amino acid with similar properties. This alteration has been reported in an individual with a personal history of breast cancer (Germani A et al. J Clin Med, 2020 Sep;9:). This amino acid position is poorly conserved in available vertebrate species. In addition, 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.
not provided Uncertain:1
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; Observed in an individual with breast cancer (PMID: 32957588); This variant is associated with the following publications: (PMID: 32957588)
Familial melanoma Uncertain:1
This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 139 of the CDKN2A (p16INK4a) protein (p.Gly139Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with CDKN2A-related cancer (PMID: 32957588). ClinVar contains an entry for this variant (Variation ID: 141419). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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