rs730881675

Variant names:

• chr9-21971105-GCGTCGTGCACGGGT-G
• rs730881675
• NM_000077.5:c.240_253delACCCGTGCACGACG

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1 PP5_Very_Strong

The NM_000077.5(CDKN2A):​c.240_253delACCCGTGCACGACG​(p.Pro81CysfsTer34) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,452,314 control chromosomes in the GnomAD database, with no homozygous occurrence. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. R80R) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CDKN2A NM_000077.5 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 9.23
• Publications: 6 publications found

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: Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics, Genomics England PanelApp
• 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

ENSG00000264545 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 9-21971105-GCGTCGTGCACGGGT-G is Pathogenic according to our data. Variant chr9-21971105-GCGTCGTGCACGGGT-G is described in ClinVar as Pathogenic. ClinVar VariationId is 182412.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000077.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CDKN2A	NM_000077.5	MANE Select	c.240_253delACCCGTGCACGACG	p.Pro81CysfsTer34	frameshift	Exon 2 of 3	NP_000068.1	P42771-1
	CDKN2A	NM_058195.4	MANE Plus Clinical	c.283_296delACCCGTGCACGACG	p.Thr95LeufsTer61	frameshift	Exon 2 of 3	NP_478102.2	Q8N726-1
	CDKN2A	NM_001195132.2		c.240_253delACCCGTGCACGACG	p.Pro81CysfsTer34	frameshift	Exon 2 of 4	NP_001182061.1	P42771-4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CDKN2A	ENST00000304494.10	TSL:1 MANE Select	c.240_253delACCCGTGCACGACG	p.Pro81CysfsTer34	frameshift	Exon 2 of 3	ENSP00000307101.5	P42771-1
	CDKN2A	ENST00000579755.2	TSL:1 MANE Plus Clinical	c.283_296delACCCGTGCACGACG	p.Thr95LeufsTer61	frameshift	Exon 2 of 3	ENSP00000462950.1	Q8N726-1
	CDKN2A	ENST00000498124.1	TSL:1	c.240_253delACCCGTGCACGACG	p.Pro81CysfsTer34	frameshift	Exon 2 of 4	ENSP00000418915.1	P42771-4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1452314 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 722888

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33440

American (AMR) AF: 0.00 AC: 0 AN: 44660

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26072

East Asian (EAS) AF: 0.00 AC: 0 AN: 39676

South Asian (SAS) AF: 0.00 AC: 0 AN: 86176

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 45034

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5446

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111552

Other (OTH) AF: 0.00 AC: 0 AN: 60258

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
4	-	-	Hereditary cancer-predisposing syndrome (4)
2	-	-	Familial melanoma (2)
2	-	-	Melanoma-pancreatic cancer syndrome (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.2
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs730881675; hg19: chr9-21971104;