12-57751337-A-G

Variant names:

• chr12-57751337-A-G
• rs748983604
• NM_000075.4:c.224T>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000075.4(CDK4):​c.224T>C​(p.Met75Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. M75V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CDK4 NM_000075.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.97
• Publications: 0 publications found

Genes affected

CDK4 (HGNC:1773): (cyclin dependent kinase 4) The protein encoded by this gene is a member of the Ser/Thr protein kinase family. This protein is highly similar to the gene products of S. cerevisiae cdc28 and S. pombe cdc2. It is a catalytic subunit of the protein kinase complex that is important for cell cycle G1 phase progression. The activity of this kinase is restricted to the G1-S phase, which is controlled by the regulatory subunits D-type cyclins and CDK inhibitor p16(INK4a). This kinase was shown to be responsible for the phosphorylation of retinoblastoma gene product (Rb). Mutations in this gene as well as in its related proteins including D-type cyclins, p16(INK4a) and Rb were all found to be associated with tumorigenesis of a variety of cancers. Multiple polyadenylation sites of this gene have been reported. [provided by RefSeq, Jul 2008]

CDK4 Gene-Disease associations (from GenCC):

• melanoma, cutaneous malignant, susceptibility to, 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), ClinGen
• malignant pancreatic neoplasm

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.781

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CDK4	NM_000075.4	c.224T>C	p.Met75Thr	missense_variant	Exon 3 of 8	ENST00000257904.11	NP_000066.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CDK4	ENST00000257904.11	c.224T>C	p.Met75Thr	missense_variant	Exon 3 of 8	1	NM_000075.4	ENSP00000257904.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461778 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727210

⚠️ 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: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53312

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ 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: 0.000111 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial melanoma Uncertain:1

Oct 03, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 75 of the CDK4 protein (p.Met75Thr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CDK4-related conditions. 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 CDK4 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.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.66
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Benign	0.29	T;T;.;T;.;.;T;.
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.50
LIST_S2	Uncertain	0.90	D;D;D;D;D;D;D;D
M_CAP	Benign	0.059	D
MetaRNN	Pathogenic	0.77	D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.50	T
MutationAssessor	Benign	0.0	.;L;.;.;.;.;.;.
PhyloP100		9.0
PrimateAI	Uncertain	0.74	T
PROVEAN	Uncertain	-3.2	D;D;D;D;D;D;D;D
Sift	Uncertain	0.0040	D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.0080	D;D;D;.;.;T;.;.
Vest4		0.62
ClinPred		0.98	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.79
gMVP		0.86
Mutation Taster		=23/77	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs748983604; hg19: chr12-58145120;