12-21882843-C-T

Variant names:

• chr12-21882843-C-T
• rs368279608
• NM_020297.4:c.1942G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_020297.4(ABCC9):​c.1942G>A​(p.Gly648Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,752 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 nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G648E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ABCC9 NM_020297.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.17
• Publications: 3 publications found

Genes affected

ABCC9 (HGNC:60): (ATP binding cassette subfamily C member 9) The protein encoded by this gene is a member of the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). This protein is a member of the MRP subfamily which is involved in multi-drug resistance. This protein is thought to form ATP-sensitive potassium channels in cardiac, skeletal, and vascular and non-vascular smooth muscle. Protein structure suggests a role as the drug-binding channel-modulating subunit of the extra-pancreatic ATP-sensitive potassium channels. Mutations in this gene are associated with cardiomyopathy dilated type 1O. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2011]

ABCC9 Gene-Disease associations (from GenCC):

• hypertrichotic osteochondrodysplasia Cantu type

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• dilated cardiomyopathy 1O

  Inheritance: AD Classification: STRONG, MODERATE, LIMITED Submitted by: Illumina, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• intellectual disability and myopathy syndrome

  Inheritance: AR Classification: MODERATE, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• acromegaloid facial appearance syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hypertrichosis-acromegaloid facial appearance syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Brugada syndrome

  Inheritance: AD Classification: LIMITED Submitted by: Genomics England PanelApp
• dilated cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• atrial fibrillation, familial, 12

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ENSG00000257022 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.272552).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020297.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCC9	NM_020297.4	MANE Select	c.1942G>A	p.Gly648Arg	missense	Exon 16 of 40	NP_064693.2
	ABCC9	NM_001377273.1		c.1942G>A	p.Gly648Arg	missense	Exon 17 of 41	NP_001364202.1
	ABCC9	NM_005691.4		c.1942G>A	p.Gly648Arg	missense	Exon 16 of 41	NP_005682.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCC9	ENST00000261200.9	TSL:5 MANE Select	c.1942G>A	p.Gly648Arg	missense	Exon 16 of 40	ENSP00000261200.4
	ABCC9	ENST00000261201.10	TSL:5	c.1942G>A	p.Gly648Arg	missense	Exon 16 of 41	ENSP00000261201.4
	ABCC9	ENST00000684084.1		c.1942G>A	p.Gly648Arg	missense	Exon 16 of 40	ENSP00000507859.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251370 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461752 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727198

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44714

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39690

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111912

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Dilated cardiomyopathy 1O Uncertain:1

Feb 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 648 of the ABCC9 protein (p.Gly648Arg). This variant is present in population databases (rs368279608, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with ABCC9-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 ABCC9 protein function with a negative predictive value of 80%. 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Uncertain	0.065	T
BayesDel_noAF	Benign	-0.14
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.31	T
Eigen	Benign	-0.11
Eigen_PC	Benign	0.080
FATHMM_MKL	Benign	0.63	D
LIST_S2	Uncertain	0.93	D
M_CAP	Uncertain	0.094	D
MetaRNN	Benign	0.27	T
MetaSVM	Uncertain	-0.12	T
MutationAssessor	Benign	0.34	N
PhyloP100		2.2
PrimateAI	Uncertain	0.61	T
PROVEAN	Benign	-0.16	N
REVEL	Benign	0.26
Sift	Benign	0.17	T
Sift4G	Benign	0.35	T
Polyphen		0.26	B
Vest4		0.47
MutPred		0.30		Gain of MoRF binding (P = 0.0165)
MVP		0.87
MPC		0.86
ClinPred		0.28	T
GERP RS		5.2
Varity_R		0.069
gMVP		0.46
Mutation Taster		=78/22	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		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: rs368279608; hg19: chr12-22035777;