9-21994211-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_058195.4(CDKN2A):​c.121G>A​(p.Ala41Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000996 in 1,605,770 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

CDKN2A
NM_058195.4 missense

Scores

1
7
9

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.73
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]
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2
High AC in GnomAdExome4 at 15 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CDKN2ANM_058195.4 linkc.121G>A p.Ala41Thr missense_variant Exon 1 of 3 ENST00000579755.2 NP_478102.2 Q8N726-1
CDKN2ANM_001363763.2 linkc.-4+610G>A intron_variant Intron 1 of 2 NP_001350692.1
CDKN2AXM_047422597.1 linkc.-4+336G>A intron_variant Intron 1 of 2 XP_047278553.1
LOC124902130XR_007061436.1 linkn.-183G>A upstream_gene_variant

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CDKN2AENST00000579755.2 linkc.121G>A p.Ala41Thr missense_variant Exon 1 of 3 1 NM_058195.4 ENSP00000462950.1 Q8N726-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152158
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1453612
Hom.:
0
Cov.:
32
AF XY:
0.0000124
AC XY:
9
AN XY:
723470
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:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000117
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152158
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
74316
show subpopulations
Gnomad4 AFR
AF:
0.00
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:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:1
Sep 20, 2019
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge; No data available from control populations to assess the frequency of this variant; Results in the change of an Alanine to a Threonine (GCC>ACC) in exon 1 of the p14-ARF protein. -

Hereditary cancer-predisposing syndrome Uncertain:1
Nov 26, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.A41T variant (also known as c.121G>A), located in coding exon 1 of the CDKN2A (p14ARF) gene, results from a G to A substitution at nucleotide position 121. The alanine at codon 41 is replaced by threonine, an amino acid with similar properties. This amino acid position is well conserved on limited sequence alignment. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Familial melanoma Uncertain:1
Jul 14, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Uncertain
0.034
T
BayesDel_noAF
Benign
-0.19
CADD
Benign
19
DANN
Uncertain
0.98
DEOGEN2
Benign
0.054
T;T
Eigen
Benign
-0.53
Eigen_PC
Benign
-0.65
FATHMM_MKL
Benign
0.094
N
LIST_S2
Benign
0.58
.;T
M_CAP
Pathogenic
0.45
D
MetaRNN
Uncertain
0.46
T;T
MetaSVM
Benign
-0.57
T
PrimateAI
Uncertain
0.67
T
PROVEAN
Uncertain
-2.8
.;D
REVEL
Uncertain
0.32
Sift
Uncertain
0.015
.;D
Sift4G
Benign
0.26
T;T
Vest4
0.37
MVP
0.92
ClinPred
0.83
D
GERP RS
2.2

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

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

Other links and lift over

dbSNP: rs1064793582; hg19: chr9-21994210; API