rs1554938197

Variant names:

• chr11-2885300-C-CCCAGCTGGAA
• rs1554938197
• NM_001122630.2:c.156_157insTTCCAGCTGG

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001122630.2(CDKN1C):​c.156_157insTTCCAGCTGG​(p.Asp53PhefsTer64) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: CDKN1C NM_001122630.2 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 1.91

Genes affected

CDKN1C (HGNC:1786): (cyclin dependent kinase inhibitor 1C) This gene is imprinted, with preferential expression of the maternal allele. The encoded protein is a tight-binding, strong inhibitor of several G1 cyclin/Cdk complexes and a negative regulator of cell proliferation. Mutations in this gene are implicated in sporadic cancers and Beckwith-Wiedemann syndorome, suggesting that this gene is a tumor suppressor candidate. Three transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, Oct 2010]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-2885300-C-CCCAGCTGGAA is Pathogenic according to our data. Variant chr11-2885300-C-CCCAGCTGGAA is described in ClinVar as [Pathogenic]. Clinvar id is 524696.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDKN1C	NM_001122630.2	c.156_157insTTCCAGCTGG	p.Asp53PhefsTer64	frameshift_variant	Exon 2 of 4	ENST00000440480.8	NP_001116102.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDKN1C	ENST00000440480.8	c.156_157insTTCCAGCTGG	p.Asp53PhefsTer64	frameshift_variant	Exon 2 of 4	1	NM_001122630.2	ENSP00000411257.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Beckwith-Wiedemann syndrome Pathogenic:1

May 18, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals with CDKN1C-related conditions. ClinVar contains an entry for this variant (Variation ID: 524696). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Asp64Phefs*64) in the CDKN1C gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CDKN1C are known to be pathogenic (PMID: 20503313). -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554938197; hg19: chr11-2906530;