11-2884682-G-T

Position:

• chr11-2884682-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_001122630.2(CDKN1C):​c.775C>A​(p.Pro259Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000765 in 1,306,866 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P259A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 7.7e-7 (0 hom.)
• Consequence: CDKN1C NM_001122630.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.544

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 Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 uncertain in NM_001122630.2
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.2639026).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CDKN1C	NM_001122630.2	c.775C>A	p.Pro259Thr	missense_variant	2/4	ENST00000440480.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CDKN1C	ENST00000440480.8	c.775C>A	p.Pro259Thr	missense_variant	2/4	1	NM_001122630.2	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.65e-7 AC: 1 AN: 1306866 Hom.: 0 Cov.: 31 AF XY: 0.00000154 AC XY: 1 AN XY: 647954

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: 9.63e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Beckwith-Wiedemann syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 23, 2023

This sequence change replaces proline, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 270 of the CDKN1C protein (p.Pro270Thr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CDKN1C-related conditions. ClinVar contains an entry for this variant (Variation ID: 454033). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CDKN1C protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Beckwith-Wiedemann syndrome;C1846009:IMAGe syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 28, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Benign	-0.032	T
BayesDel_noAF	Benign	-0.28
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.059	T;T;.
Eigen	Benign	-0.17
Eigen_PC	Benign	-0.29
FATHMM_MKL	Benign	0.054	N
LIST_S2	Benign	0.54	.;T;T
M_CAP	Pathogenic	0.99	D
MetaRNN	Benign	0.26	T;T;T
MetaSVM	Uncertain	-0.27	T
MutationAssessor	Benign	0.81	L;L;.
MutationTaster	Benign	1.0	D;N;N;N;N
PrimateAI	Pathogenic	0.89	D
PROVEAN	Benign	-1.1	N;N;N
REVEL	Uncertain	0.34
Sift	Benign	0.031	D;D;D
Sift4G	Uncertain	0.051	T;T;T
Polyphen		0.99	D;D;.
Vest4		0.20
MutPred		0.30		Loss of stability (P = 0.0496);Loss of stability (P = 0.0496);.;
MVP		0.48
MPC		1.4
ClinPred		0.31	T
GERP RS		0.98
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2
Varity_R		0.17
gMVP		0.24

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: rs1416211722; hg19: chr11-2905912;