chr7-87439765-G-C

Variant names:

• chr7-87439765-G-C
• rs397514620
• NM_000443.4:c.1633C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM2 PM5 PP2 PP3_Strong

The NM_000443.4(ABCB4):​c.1633C>G​(p.Arg545Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. R545H) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ABCB4 NM_000443.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts P:1 U:2
• Conservation: PhyloP100: 3.23
• Publications: 6 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), ClinGen, Orphanet
• gallbladder disease 1

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

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-87439764-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2687819.
• PP2: Missense variant in the ABCB4 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 32 curated pathogenic missense variants (we use a threshold of 10). The gene has 6 curated benign missense variants. Gene score misZ: 1.9749 (below the threshold of 3.09). Trascript score misZ: 3.5425 (above the threshold of 3.09). GenCC associations: The gene is linked to gallbladder disease 1, progressive familial intrahepatic cholestasis type 3, pancreatitis.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCB4	NM_000443.4	MANE Select	c.1633C>G	p.Arg545Gly	missense	Exon 14 of 28	NP_000434.1
	ABCB4	NM_018849.3		c.1633C>G	p.Arg545Gly	missense	Exon 14 of 28	NP_061337.1
	ABCB4	NM_018850.3		c.1633C>G	p.Arg545Gly	missense	Exon 14 of 27	NP_061338.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABCB4	ENST00000649586.2	MANE Select	c.1633C>G	p.Arg545Gly	missense	Exon 14 of 28	ENSP00000496956.2
	ABCB4	ENST00000265723.8	TSL:1	c.1633C>G	p.Arg545Gly	missense	Exon 14 of 28	ENSP00000265723.4
	ABCB4	ENST00000359206.8	TSL:1	c.1633C>G	p.Arg545Gly	missense	Exon 14 of 28	ENSP00000352135.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	-	-	Low phospholipid associated cholelithiasis (1)
-	1	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
CADD	Uncertain	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Uncertain	0.43
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Pathogenic	0.97	D
M_CAP	Pathogenic	0.75	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.0	M
PhyloP100		3.2
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-6.3	D
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.96
MutPred		0.95		Loss of MoRF binding (P = 0.0099)
MVP		0.90
MPC		1.1
ClinPred		0.98	D
GERP RS		3.7
Varity_R		0.98
gMVP		0.97
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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: rs397514620; hg19: chr7-87069081;