9-21994165-C-T

Position:

chr9-21994165-C-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_058195.4(CDKN2A):c.167G>A(p.Gly56Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000306 in 1,603,288 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000032 ( 0 hom. )

Consequence

CDKN2A
NM_058195.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 1.78

Variant links:

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]

CDKN2A links:

CDKN2B-AS1 (HGNC:34341): (CDKN2B antisense RNA 1) This gene is located within the CDKN2B-CDKN2A gene cluster at chromosome 9p21. The gene product is a functional RNA molecule that interacts with polycomb repressive complex-1 (PRC1) and -2 (PRC2), leading to epigenetic silencing of other genes in this cluster. This region is a significant genetic susceptibility locus for cardiovascular disease, and has also been linked to a number of other pathologies, including several cancers, intracranial aneurysm, type-2 diabetes, periodontitis, Alzheimer's disease, endometriosis, frailty in the elderly, and glaucoma. Multiple alternatively processed transcript variants have been detected, some of which may take the form of circular RNA molecules (PMID:21151960). [provided by RefSeq, May 2014]

CDKN2B-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.23876435).

BS2

High AC in GnomAdExome4 at 46 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
CDKN2A	NM_058195.4 linkuse as main transcript	c.167G>A	p.Gly56Glu	missense_variant	1/3	ENST00000579755.2	NP_478102.2
CDKN2A	NM_001363763.2 linkuse as main transcript	c.-4+656G>A		intron_variant			NP_001350692.1
CDKN2A	XM_047422597.1 linkuse as main transcript	c.-4+382G>A		intron_variant			XP_047278553.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDKN2A	ENST00000579755.2 linkuse as main transcript	c.167G>A	p.Gly56Glu	missense_variant	1/3	1	NM_058195.4	ENSP00000462950		Q8N726-1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152220

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000855

AC:

AN:

233810

Hom.:

AF XY:

0.00000773

AC XY:

AN XY:

129382

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000186

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000317

AC:

AN:

1451068

Hom.:

Cov.:

AF XY:

0.0000318

AC XY:

AN XY:

722378

show subpopulations

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:

0.0000414

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152220

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74366

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000673

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.00000828

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Melanoma-pancreatic cancer syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Apr 21, 2023	This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Apr 19, 2018	- -

Hereditary cancer-predisposing syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Jul 13, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 03, 2024	The p.G56E variant (also known as c.167G>A), located in coding exon 1 of the CDKN2A (p14ARF) gene, results from a G to A substitution at nucleotide position 167. The glycine at codon 56 is replaced by glutamic acid, an amino acid with similar properties. This alteration was identified in 2/1358 non-cancer control individuals and in 0/57 cases, in a study looking at cancer predisposition mutations in patients with cutaneous melanoma and a history of at least two additional non-cutaneous melanoma primary cancers (Pritchard AL et al. PLoS One, 2018 Apr;13:e0194098). This amino acid position is not well conserved in available vertebrate species. Based on the available evidence, the clinical significance of this variant remains unclear. -

Melanoma and neural system tumor syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Dec 25, 2023

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

May 26, 2023

This variant in the p14-ARF isoform is not expected to affect the p16 protein; Observed among control individuals in a melanoma case-control study (Pritchard et al., 2018); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 29641532, 9653180, 9529249, 16173922) -

Familial melanoma

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 24, 2020

This sequence change replaces glycine with glutamic acid at codon 56 of the CDKN2A (p14ARF) protein (p.Gly56Glu). The glycine residue is moderately conserved and there is a moderate physicochemical difference between glycine and glutamic acid. This variant is present in population databases (rs748327367, ExAC 0.002%). This variant has not been reported in the literature in individuals with CDKN2A (p14ARF)-related disease. ClinVar contains an entry for this variant (Variation ID: 463514) Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: Deleterious; PolyPhen-2: Probably Damaging; Align-GVGD: Class C0). 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

Benign

-0.026

BayesDel_noAF

Benign

-0.26

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.026

T;T

Eigen

Benign

0.0044

Eigen_PC

Benign

0.026

FATHMM_MKL

Benign

0.35

LIST_S2

Benign

0.55

.;T

M_CAP

Uncertain

0.13

MetaRNN

Benign

0.24

T;T

MetaSVM

Benign

-0.70

MutationTaster

Benign

1.0

D;D;N;N;N

PrimateAI

Uncertain

0.67

PROVEAN

Uncertain

-2.6

.;D

REVEL

Benign

0.22

Sift

Benign

0.063

.;T

Sift4G

Benign

0.13

T;T

Vest4

0.21

MVP

0.99

ClinPred

0.74

GERP RS

2.7

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over