9-21971167-C-G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1PM2BP6_Moderate

The NM_058195.4(CDKN2A):​c.235G>C​(p.Ala79Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000693 in 1,442,940 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely benign (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A79S) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

CDKN2A
NM_058195.4 missense

Scores

1
9
8

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 1.73

Publications

2 publications found
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 Gene-Disease associations (from GenCC):
  • melanoma, cutaneous malignant, susceptibility to, 2
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • melanoma-pancreatic cancer syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • familial atypical multiple mole melanoma syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • melanoma and neural system tumor syndrome
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM1
In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 18 benign, 32 uncertain in NM_058195.4
PM2
Very rare variant in population databases, with high coverage;
BP6
Variant 9-21971167-C-G is Benign according to our data. Variant chr9-21971167-C-G is described in ClinVar as Likely_benign. ClinVar VariationId is 3999775.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CDKN2ANM_058195.4 linkc.235G>C p.Ala79Pro missense_variant Exon 2 of 3 ENST00000579755.2 NP_478102.2 Q8N726-1
CDKN2ANM_000077.5 linkc.192G>C p.Leu64Leu synonymous_variant Exon 2 of 3 ENST00000304494.10 NP_000068.1 P42771-1K7PML8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CDKN2AENST00000579755.2 linkc.235G>C p.Ala79Pro missense_variant Exon 2 of 3 1 NM_058195.4 ENSP00000462950.1 Q8N726-1
CDKN2AENST00000304494.10 linkc.192G>C p.Leu64Leu synonymous_variant Exon 2 of 3 1 NM_000077.5 ENSP00000307101.5 P42771-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.93e-7
AC:
1
AN:
1442940
Hom.:
0
Cov.:
31
AF XY:
0.00000139
AC XY:
1
AN XY:
718012
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33300
American (AMR)
AF:
0.00
AC:
0
AN:
44232
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25986
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39364
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85676
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
39280
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5374
European-Non Finnish (NFE)
AF:
9.01e-7
AC:
1
AN:
1109806
Other (OTH)
AF:
0.00
AC:
0
AN:
59922
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Likely benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:1
May 24, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Uncertain
0.089
D
BayesDel_noAF
Benign
-0.11
CADD
Benign
9.6
DANN
Uncertain
1.0
DEOGEN2
Benign
0.078
T;T
Eigen
Uncertain
0.25
Eigen_PC
Uncertain
0.23
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.54
.;T
M_CAP
Pathogenic
0.29
D
MetaRNN
Uncertain
0.50
D;D
MetaSVM
Benign
-0.45
T
PhyloP100
1.7
PrimateAI
Uncertain
0.50
T
PROVEAN
Uncertain
-3.2
.;D
REVEL
Uncertain
0.42
Sift
Benign
0.089
.;T
Sift4G
Benign
0.15
T;T
Vest4
0.43
MVP
0.93
ClinPred
0.57
D
GERP RS
3.9
PromoterAI
-0.0092
Neutral
Mutation Taster
=2/98
disease causing

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

Other links and lift over

dbSNP: rs876659128; hg19: chr9-21971166; API