rs587777618

Variant names:

• chr12-4299977-A-C
• rs587777618
• NM_001759.4:c.838A>C

Your query was ambiguous. Multiple possible variants found:

• chr12-4299977-A-C
• chr12-4299977-A-G

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP5_Moderate

The NM_001759.4(CCND2):​c.838A>C​(p.Thr280Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T280I) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CCND2 NM_001759.4 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.49
• Publications: 0 publications found

Genes affected

CCND2 (HGNC:1583): (cyclin D2) The protein encoded by this gene belongs to the highly conserved cyclin family, whose members are characterized by a dramatic periodicity in protein abundance through the cell cycle. Cyclins function as regulators of CDK kinases. Different cyclins exhibit distinct expression and degradation patterns which contribute to the temporal coordination of each mitotic event. This cyclin forms a complex with CDK4 or CDK6 and functions as a regulatory subunit of the complex, whose activity is required for cell cycle G1/S transition. This protein has been shown to interact with and be involved in the phosphorylation of tumor suppressor protein Rb. Knockout studies of the homologous gene in mouse suggest the essential roles of this gene in ovarian granulosa and germ cell proliferation. High level expression of this gene was observed in ovarian and testicular tumors. Mutations in this gene are associated with megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome 3 (MPPH3). [provided by RefSeq, Sep 2014]

CCND2 Gene-Disease associations (from GenCC):

• megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
• megalencephaly-polymicrogyria-postaxial polydactyly-hydrocephalus syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000285901 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001759.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-4299978-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 666559.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP5: Variant 12-4299977-A-C is Pathogenic according to our data. Variant chr12-4299977-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 3254550.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CCND2	NM_001759.4	c.838A>C	p.Thr280Pro	missense_variant	Exon 5 of 5	ENST00000261254.8	NP_001750.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CCND2	ENST00000261254.8	c.838A>C	p.Thr280Pro	missense_variant	Exon 5 of 5	1	NM_001759.4	ENSP00000261254.3
ENSG00000285901	ENST00000674624.1	n.720+10987A>C		intron_variant	Intron 4 of 9			ENSP00000501898.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome 3 Pathogenic:1

Jul 17, 2023

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0101 - Gain of function is a known mechanism of disease in this gene and is associated with megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome 3 (MIM#615938) (PMID: 24705253). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from threonine to proline. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (1 heterozygote, 0 homozygotes). (I) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0602 - Variant is located in a hotspot region or cluster of pathogenic variants at the end of the cyclin C-terminal domain (DECIPHER). (SP) 0701 - Other missense variants comparable to the one identified in this case have very strong previous evidence for pathogenicity. Three alternative amino acid substitutions at the same position, p.(Thr280Ala), p.(Thr280Asn) and p.(Thr280Ile), have been classified as pathogenic or likely pathogenic by multiple clinical laboratories in ClinVar. (SP) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1101 - Very strong and specific phenotype match for this individual. (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.79
BayesDel_addAF	Uncertain	0.069	T
BayesDel_noAF	Benign	-0.14
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.90	D
M_CAP	Uncertain	0.19	D
MetaRNN	Uncertain	0.67	D
MetaSVM	Benign	-0.87	T
MutationAssessor	Pathogenic	3.4	M
PhyloP100		8.5
PrimateAI	Uncertain	0.55	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Uncertain	0.46
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.52
MutPred		0.63		Gain of catalytic residue at T280 (P = 0.0275);
MVP		0.70
MPC		2.4
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.87
gMVP		0.73
Mutation Taster		=7/93	disease causing

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: rs587777618; hg19: chr12-4409143;