rs752685118

chr9-21971065-G-Achr9-21971065-G-C

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP6

The NM_058195.4(CDKN2A):c.337C>T(p.Pro113Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,453,252 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/16 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P113Q) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CDKN2A NM_058195.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:2
• Conservation: PhyloP100: 0.780

Genes affected

CDKN2A (HGNC:1787): (cyclin dependent kinase inhibitor 2A) This gene generates several transcript variants which differ in their first exons. At least three alternatively spliced variants encoding distinct proteins have been reported, two of which encode structurally related isoforms known to function as inhibitors of CDK4 kinase. The remaining transcript includes an alternate first exon located 20 Kb upstream of the remainder of the gene; this transcript contains an alternate open reading frame (ARF) that specifies a protein which is structurally unrelated to the products of the other variants. This ARF product functions as a stabilizer of the tumor suppressor protein p53 as it can interact with, and sequester, the E3 ubiquitin-protein ligase MDM2, a protein responsible for the degradation of p53. In spite of the structural and functional differences, the CDK inhibitor isoforms and the ARF product encoded by this gene, through the regulatory roles of CDK4 and p53 in cell cycle G1 progression, share a common functionality in cell cycle G1 control. This gene is frequently mutated or deleted in a wide variety of tumors, and is known to be an important tumor suppressor gene. [provided by RefSeq, Sep 2012]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11611533).
• BP6: Variant 9-21971065-G-A is Benign according to our data. Variant chr9-21971065-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 463515.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=2, Likely_benign=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CDKN2A	NM_058195.4	c.337C>T	p.Pro113Ser	missense_variant	2/3	ENST00000579755.2
CDKN2A	NM_000077.5	c.294C>T	p.His98=	synonymous_variant	2/3	ENST00000304494.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CDKN2A	ENST00000579755.2	c.337C>T	p.Pro113Ser	missense_variant	2/3	1	NM_058195.4
CDKN2A	ENST00000304494.10	c.294C>T	p.His98=	synonymous_variant	2/3	1	NM_000077.5	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1453252 Hom.: 0 Cov.: 31 AF XY: 0.00000415 AC XY: 3 AN XY: 723276

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000835 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 17, 2018	- -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 25, 2020	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Melanoma, cutaneous malignant, susceptibility to, 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Mendelics

Jul 02, 2018

- -

Familial melanoma Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 10, 2020

This sequence change replaces proline with serine at codon 113 of the CDKN2A (p14ARF) protein (p.Pro113Ser). The proline residue is moderately conserved and there is a moderate physicochemical difference between proline and serine. This variant is present in population databases (rs752685118, ExAC 0.002%). This variant has been observed in several individuals affected with primary cutaneous melanoma (PMID: 26775776, 29464027). ClinVar contains an entry for this variant (Variation ID: 463515). 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. 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: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.024	T
BayesDel_noAF	Benign	-0.20
Cadd	Benign	7.1
Dann	Benign	0.94
DEOGEN2	Benign	0.066	T;T
Eigen	Benign	-0.46
Eigen_PC	Benign	-0.33
FATHMM_MKL	Benign	0.66	D
M_CAP	Benign	0.084	D
MetaRNN	Benign	0.12	T;T
MetaSVM	Benign	-0.89	T
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;N;N;N
PrimateAI	Benign	0.42	T
Sift4G	Benign	0.53	T;T
Vest4		0.15
MVP		0.83
ClinPred		0.020	T
GERP RS		3.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs752685118; hg19: chr9-21971064; COSMIC: COSV58686124; COSMIC: COSV58686124;