rs864622263

Positions:

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PM5PP3_ModeratePP5_Very_Strong

The ENST00000304494.10(CDKN2A):c.47T>G(p.Leu16Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000687 in 1,455,866 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L16P) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

CDKN2A
ENST00000304494.10 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 5.50

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:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 16 uncertain in ENST00000304494.10

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr9-21974781-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 649266.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.902

PP5

Variant 9-21974781-A-C is Pathogenic according to our data. Variant chr9-21974781-A-C is described in ClinVar as [Pathogenic]. Clinvar id is 219815.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-21974781-A-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CDKN2A	NM_000077.5 linkuse as main transcript	c.47T>G	p.Leu16Arg	missense_variant	1/3	ENST00000304494.10	NP_000068.1
CDKN2A	NM_058195.4 linkuse as main transcript	c.194-3573T>G		intron_variant		ENST00000579755.2	NP_478102.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDKN2A	ENST00000304494.10 linkuse as main transcript	c.47T>G	p.Leu16Arg	missense_variant	1/3	1	NM_000077.5	ENSP00000307101	P2	P42771-1
CDKN2A	ENST00000579755.2 linkuse as main transcript	c.194-3573T>G		intron_variant		1	NM_058195.4	ENSP00000462950		Q8N726-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.87e-7

AC:

AN:

1455866

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

724558

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:

9.00e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Feb 29, 2024	Published functional studies demonstrate a damaging effect: impaired cell cycle control and abolished interaction with CDK4 and CDK6 (PMID: 33823155); 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: 30039340, 12072543, 9425228, 21150883, 21462282, 17047042, 16234564, 20340136, 15173226, 16896043, 20876876, 10861313, 16905682, 16172233, 25356972, 17218939, 28726808, 29922827, 28830827, 29661971, 34399810, 32482799, 33823155) -
Pathogenic, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Pathogenic, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -

Hereditary cancer-predisposing syndrome

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 10, 2022	The CDKN2A locus encodes two different gene products, p16INK4a and p14ARF (https://www.ncbi.nlm.nih.gov/books/NBK7030/). This missense variant replaces leucine with arginine at codon 16 of the CDKN2A (p16INK4A) protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). A functional study has shown that this variant results in reduced protein expression levels, inability to bind CDK4/CDK6, and impairment of the cell cycle control activity (PMID: 33823155). This variant has been reported in individuals and families affected with melanoma (PMID: 10861313, 12072543, 15146471, 15173226, 16169933, 16172233, 16234564, 16896043, 17218939, 21150883, 21462282, 25685612) and pancreatic cancer (PMID: 25356972). This variant has been observed in four multi-generational families affected with malignant melanoma and pancreatic cancer, where this variant has shown segregation with cancers in an autosomal dominant manner (PMID: 33823155). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). A different missense variant at this position, p.Leu16Pro, has been shown to impair p16INK4A protein function and is classified as Pathogenic (PMID: 20340136; ClinVar variation ID: 649266), indicating that leucine at this position is important for p16INK4A protein function. Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 10, 2021	The p.L16R pathogenic mutation (also known as c.47T>G), located in coding exon 1 of the CDKN2A gene, results from a T to G substitution at nucleotide position 47. The leucine at codon 16 is replaced by arginine, an amino acid with dissimilar properties. This mutation has been observed in multiple individuals with personal and/or family history of melanoma and/or pancreatic cancer (Goldstein AM et al. J. Natl. Cancer Inst. 2000 Jun; 92(12):1006-10; Miller PJ et al. Hum. Mutat. 2011 Aug; 32(8):900-11; Horn IP et al. J Biol Chem 2021 Apr;296:100634; Overbeek KA et al. J Med Genet, 2021 04;58:264-269; Ambry internal data) and has been shown to segregate with disease in several melanoma families (Goldstein AM et al. J. Natl. Cancer Inst. 2000 Jun; 92(12):1006-10; Miller PJ et al. Hum. Mutat. 2011 Aug; 32(8):900-11). Another pathogenic alteration impacting the same codon, p.L16P, has also been observed to segregate with melanoma in several families (Soufir N et al. Hum. Mol. Genet. 1998 Feb; 7(2):209-16; Miller PJ et al. Hum. Mutat. 2011 Aug; 32(8):900-11) and has been associated with protein mislocalization and reduced binding to CDK4 and CDK6 (McKenzie HA et al. Hum. Mutat. 2010 Jun; 31(6):692-701). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Familial melanoma

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 09, 2023

This sequence change replaces leucine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 16 of the CDKN2A (p16INK4a) protein (p.Leu16Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with melanoma and pancreatic cancer (PMID: 15173226, 16169933, 17218939, 21150883; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 219815). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. This variant disrupts the p.Leu16 amino acid residue in CDKN2A (p16INK4a). Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 17624602, 20340136, 21462282). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.84

BayesDel_addAF

Pathogenic

0.39

BayesDel_noAF

Pathogenic

0.33

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.60

D;T;.

Eigen

Uncertain

0.39

Eigen_PC

Benign

0.14

FATHMM_MKL

Uncertain

0.91

LIST_S2

Benign

0.74

T;T;T

M_CAP

Pathogenic

0.67

MetaRNN

Pathogenic

0.90

D;D;D

MetaSVM

Uncertain

0.32

MutationTaster

Benign

1.0

N;N;N;N;N;N;N;N;N

PrimateAI

Uncertain

0.75

PROVEAN

Pathogenic

-4.8

D;.;D

REVEL

Uncertain

0.57

Sift

Uncertain

0.025

D;.;D

Sift4G

Uncertain

0.028

D;D;D

Polyphen

1.0

D;.;.

Vest4

0.96

MutPred

0.56

Gain of methylation at L16 (P = 0.0266);Gain of methylation at L16 (P = 0.0266);Gain of methylation at L16 (P = 0.0266);

MVP

0.98

MPC

1.5

ClinPred

0.99

GERP RS

3.7

Varity_R

0.77

gMVP

1.0

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

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