12-21805251-C-CA

Variant names:

• chr12-21805251-C-CA
• rs761784169
• NM_020297.4:c.4512+746_4512+747insT

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_005691.4(ABCC9):​c.4572_4573insT​(p.Val1525CysfsTer4) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ABCC9 NM_005691.4 frameshift
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:2 B:2
• Conservation: PhyloP100: 2.30
• Publications: 2 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)

KCNJ8-AS1 (HGNC:58193):

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005691.4. 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.4512+746_4512+747insT		intron	N/A	NP_064693.2
	ABCC9	NM_005691.4		c.4572_4573insT	p.Val1525CysfsTer4	frameshift	Exon 40 of 41	NP_005682.2
	ABCC9	NM_001377273.1		c.4512+746_4512+747insT		intron	N/A	NP_001364202.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCC9	ENST00000261200.9	TSL:5 MANE Select	c.4512+746_4512+747insT		intron	N/A	ENSP00000261200.4
	ABCC9	ENST00000261201.10	TSL:5	c.4572_4573insT	p.Val1525CysfsTer4	frameshift	Exon 40 of 41	ENSP00000261201.4
	ABCC9	ENST00000544039.5	TSL:5	c.3453_3454insT	p.Val1152CysfsTer4	frameshift	Exon 31 of 31	ENSP00000440521.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Alfa AF: 0.000759 Hom.: 0

Bravo AF: 0.000431

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Cardiomyopathy (1)
-	-	1	Dilated cardiomyopathy 1O (1)
1	-	-	Hypertrichotic osteochondrodysplasia Cantu type;C1837839:Dilated cardiomyopathy 1O;C3279695:Atrial fibrillation, familial, 12 (1)
-	1	-	Intellectual disability (1)
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.3
Mutation Taster		=4/196	disease causing (ClinVar)

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: rs761784169; hg19: chr12-21958185;