9-21973423-G-T

Position:

• chr9-21973423-G-T

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BA1

The NM_000077.5(CDKN2A):​c.150+1255C>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.248 in 151,872 control chromosomes in the GnomAD database, including 4,738 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency: Genomes: 𝑓 0.25 (4738 hom., cov: 32)
• Consequence: CDKN2A NM_000077.5 intron
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: -0.892

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 Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.96).
• BP6: Variant 9-21973423-G-T is Benign according to our data. Variant chr9-21973423-G-T is described in ClinVar as [Benign]. Clinvar id is 254882.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BA1: GnomAd4 highest subpopulation (NFE) allele frequency at 95% confidence interval = 0.258 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CDKN2A	NM_000077.5	c.150+1255C>A		intron_variant		ENST00000304494.10
CDKN2A	NM_058195.4	c.194-2215C>A		intron_variant		ENST00000579755.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CDKN2A	ENST00000304494.10	c.150+1255C>A		intron_variant		1	NM_000077.5	P2
CDKN2A	ENST00000579755.2	c.194-2215C>A		intron_variant		1	NM_058195.4

Frequencies

GnomAD3 genomes AF: 0.248 AC: 37647 AN: 151754 Hom.: 4734 Cov.: 32

Gnomad AFR AF: 0.253

Gnomad AMI AF: 0.348

Gnomad AMR AF: 0.211

Gnomad ASJ AF: 0.292

Gnomad EAS AF: 0.211

Gnomad SAS AF: 0.161

Gnomad FIN AF: 0.229

Gnomad MID AF: 0.314

Gnomad NFE AF: 0.261

Gnomad OTH AF: 0.267

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.248 AC: 37691 AN: 151872 Hom.: 4738 Cov.: 32 AF XY: 0.244 AC XY: 18124 AN XY: 74206

Gnomad4 AFR AF: 0.253

Gnomad4 AMR AF: 0.211

Gnomad4 ASJ AF: 0.292

Gnomad4 EAS AF: 0.211

Gnomad4 SAS AF: 0.161

Gnomad4 FIN AF: 0.229

Gnomad4 NFE AF: 0.261

Gnomad4 OTH AF: 0.270

Alfa AF: 0.234 Hom.: 2848

Bravo AF: 0.250

ClinVar

Significance: Benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:1

Benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

-

- -

not provided Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

Jan 10, 2019

- -

Melanoma-pancreatic cancer syndrome Benign:1

Benign, criteria provided, single submitter

clinical testing

KCCC/NGS Laboratory, Kuwait Cancer Control Center

Jul 07, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.96
CADD	Benign	2.2
DANN	Benign	0.40

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: rs2811708; hg19: chr9-21973422;