12-12718180-C-T

Variant names:

• chr12-12718180-C-T
• rs755989911
• NM_004064.5:c.341C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_004064.5(CDKN1B):​c.341C>T​(p.Pro114Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,776 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict 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. P114R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CDKN1B NM_004064.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: -0.304
• Publications: 0 publications found

Genes affected

CDKN1B (HGNC:1785): (cyclin dependent kinase inhibitor 1B) This gene encodes a cyclin-dependent kinase inhibitor, which shares a limited similarity with CDK inhibitor CDKN1A/p21. The encoded protein binds to and prevents the activation of cyclin E-CDK2 or cyclin D-CDK4 complexes, and thus controls the cell cycle progression at G1. The degradation of this protein, which is triggered by its CDK dependent phosphorylation and subsequent ubiquitination by SCF complexes, is required for the cellular transition from quiescence to the proliferative state. Mutations in this gene are associated with multiple endocrine neoplasia type IV (MEN4). [provided by RefSeq, Apr 2014]

CDKN1B Gene-Disease associations (from GenCC):

• multiple endocrine neoplasia type 4

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet, ClinGen
• multiple endocrine neoplasia

  Inheritance: AD Classification: STRONG Submitted by: G2P
• hereditary nonpolyposis colon cancer

  Inheritance: AR Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.06311098).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDKN1B	NM_004064.5	c.341C>T	p.Pro114Leu	missense_variant	Exon 1 of 3	ENST00000228872.9	NP_004055.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDKN1B	ENST00000228872.9	c.341C>T	p.Pro114Leu	missense_variant	Exon 1 of 3	1	NM_004064.5	ENSP00000228872.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460776 Hom.: 0 Cov.: 39 AF XY: 0.00000413 AC XY: 3 AN XY: 726672

African (AFR) AF: 0.00 AC: 0 AN: 33386

American (AMR) AF: 0.00 AC: 0 AN: 44652

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52840

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5726

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111750

Other (OTH) AF: 0.00 AC: 0 AN: 60354

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Multiple endocrine neoplasia type 4 Uncertain:2

Mar 11, 2024

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 10, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 114 of the CDKN1B protein (p.Pro114Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CDKN1B-related conditions. ClinVar contains an entry for this variant (Variation ID: 1731246). 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 tolerated. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Aug 14, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.341C>T (p.P114L) alteration is located in exon 1 (coding exon 1) of the CDKN1B gene. This alteration results from a C to T substitution at nucleotide position 341, causing the proline (P) at amino acid position 114 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.069
BayesDel_addAF	Benign	-0.17	T
BayesDel_noAF	Benign	-0.49
CADD	Benign	15
DANN	Benign	0.96
DEOGEN2	Uncertain	0.57	D;T
Eigen	Benign	-0.95
Eigen_PC	Benign	-0.95
FATHMM_MKL	Benign	0.30	N
LIST_S2	Benign	0.82	T;T
M_CAP	Benign	0.027	D
MetaRNN	Benign	0.063	T;T
MetaSVM	Benign	-0.95	T
MutationAssessor	Benign	1.2	L;.
PhyloP100		-0.30
PrimateAI	Benign	0.36	T
PROVEAN	Uncertain	-3.0	D;D
REVEL	Benign	0.16
Sift	Uncertain	0.017	D;D
Sift4G	Benign	0.21	T;T
Polyphen		0.16	B;.
Vest4		0.069
MutPred		0.26		Loss of glycosylation at P114 (P = 0.0499);Loss of glycosylation at P114 (P = 0.0499);
MVP		0.40
MPC		0.075
ClinPred		0.21	T
GERP RS		-5.4
PromoterAI		0.019	Neutral
Varity_R		0.13
gMVP		0.34
Mutation Taster		=91/9	polymorphism

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

Other links and lift over

dbSNP: rs755989911; hg19: chr12-12871114;