7-87420029-C-G

Position:

• chr7-87420029-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000443.4(ABCB4):​c.2363G>C​(p.Arg788Pro) 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R788Q) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ABCB4 NM_000443.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.85

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a domain ABC transmembrane type-1 2 (size 288) in uniprot entity MDR3_HUMAN there are 25 pathogenic changes around while only 2 benign (93%) in NM_000443.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), ABCB4. . Gene score misZ 1.9749 (greater than the threshold 3.09). Trascript score misZ 3.5425 (greater than threshold 3.09). GenCC has associacion of gene with pancreatitis, low phospholipid associated cholelithiasis, progressive familial intrahepatic cholestasis type 3.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.961

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ABCB4	NM_000443.4	c.2363G>C	p.Arg788Pro	missense_variant	19/28	ENST00000649586.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ABCB4	ENST00000649586.2	c.2363G>C	p.Arg788Pro	missense_variant	19/28		NM_000443.4	P1
ABCB4	ENST00000265723.8	c.2363G>C	p.Arg788Pro	missense_variant	19/28	1
ABCB4	ENST00000359206.8	c.2363G>C	p.Arg788Pro	missense_variant	19/28	1		P1
ABCB4	ENST00000453593.5	c.2363G>C	p.Arg788Pro	missense_variant	18/26	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	.;.;D;.;.
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Pathogenic	0.99	.;D;D;D;.
M_CAP	Pathogenic	0.46	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	4.3	H;H;H;H;H
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Pathogenic	-6.1	.;D;D;D;D
REVEL	Pathogenic	0.78
Sift	Pathogenic	0.0	.;D;D;D;D
Sift4G	Pathogenic	0.0010	.;D;D;D;D
Polyphen		1.0	D;.;D;D;.
Vest4		0.88, 0.90, 0.91, 0.88
MutPred		0.78		Loss of MoRF binding (P = 0.0015);Loss of MoRF binding (P = 0.0015);Loss of MoRF binding (P = 0.0015);Loss of MoRF binding (P = 0.0015);Loss of MoRF binding (P = 0.0015);
MVP		0.91
MPC		1.2
ClinPred		1.0	D
GERP RS		4.2
Varity_R		0.99
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs8187801; hg19: chr7-87049345;