7-87411948-G-A

Variant names:

• chr7-87411948-G-A
• rs121918440
• NM_000443.4:c.2869C>T

Variant summary

Our verdict is Pathogenic. The variant received 20 ACMG points: 20P and 0B. PVS1 PS3 PP5_Very_Strong

The NM_000443.4(ABCB4):​c.2869C>T​(p.Arg957*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,706 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 Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000915234: Canalicular staining for ABCB4 protein was negative in liver tissue of the homozygous proband, and Northern blot and Western blot analysis showed low level or absence of RNA and protein (de Vree et al. 1998).". Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: ABCB4 NM_000443.4 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 2.27
• Publications: 4 publications found

Genes affected

ABCB4 (HGNC:45): (ATP binding cassette subfamily B member 4) The membrane-associated 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 MDR/TAP subfamily. Members of the MDR/TAP subfamily are involved in multidrug resistance as well as antigen presentation. This gene encodes a full transporter and member of the p-glycoprotein family of membrane proteins with phosphatidylcholine as its substrate. The function of this protein has not yet been determined; however, it may involve transport of phospholipids from liver hepatocytes into bile. Alternative splicing of this gene results in several products of undetermined function. [provided by RefSeq, Jul 2008]

ABCB4 Gene-Disease associations (from GenCC):

• progressive familial intrahepatic cholestasis type 3

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
• gallbladder disease 1

  Inheritance: SD, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
• pancreatitis

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 20 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PS3: PS3 evidence extracted from ClinVar submissions: SCV000915234: Canalicular staining for ABCB4 protein was negative in liver tissue of the homozygous proband, and Northern blot and Western blot analysis showed low level or absence of RNA and protein (de Vree et al. 1998).
• PP5: Variant 7-87411948-G-A is Pathogenic according to our data. Variant chr7-87411948-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 13687.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000443.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCB4	NM_000443.4	MANE Select	c.2869C>T	p.Arg957*	stop_gained	Exon 23 of 28	NP_000434.1	P21439-2
	ABCB4	NM_018849.3		c.2869C>T	p.Arg957*	stop_gained	Exon 23 of 28	NP_061337.1	P21439-1
	ABCB4	NM_018850.3		c.2783+1669C>T		intron	N/A	NP_061338.1	P21439-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCB4	ENST00000649586.2	MANE Select	c.2869C>T	p.Arg957*	stop_gained	Exon 23 of 28	ENSP00000496956.2	P21439-2
	ABCB4	ENST00000265723.8	TSL:1	c.2869C>T	p.Arg957*	stop_gained	Exon 23 of 28	ENSP00000265723.4	P21439-1
	ABCB4	ENST00000359206.8	TSL:1	c.2869C>T	p.Arg957*	stop_gained	Exon 23 of 28	ENSP00000352135.3	P21439-2

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152140 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461566 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727076

African (AFR) AF: 0.00 AC: 0 AN: 33474

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39662

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111802

Other (OTH) AF: 0.0000166 AC: 1 AN: 60372

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152140 Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2 AN XY: 74322

African (AFR) AF: 0.0000724 AC: 3 AN: 41438

American (AMR) AF: 0.00 AC: 0 AN: 15262

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2086

Alfa AF: 0.0000310 Hom.: 0

Bravo AF: 0.0000151

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	not provided (2)
1	-	-	Cholestasis, intrahepatic, of pregnancy, 3 (1)
1	-	-	Low phospholipid associated cholelithiasis (1)
1	-	-	Progressive familial intrahepatic cholestasis type 3 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Uncertain	0.65
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Uncertain	0.87	D
PhyloP100		2.3
Vest4		0.90
GERP RS		3.7
Mutation Taster		=0/200	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: rs121918440; hg19: chr7-87041264; COSMIC: COSV55934187; COSMIC: COSV55934187;