chr2-168924730-C-A

Variant names:

• chr2-168924730-C-A
• NM_003742.4:c.3692G>T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_003742.4(ABCB11):​c.3692G>T​(p.Arg1231Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,582 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ABCB11 NM_003742.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.91

Genes affected

ABCB11 (HGNC:42): (ATP binding cassette subfamily B member 11) 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. The protein encoded by this gene is the major canalicular bile salt export pump in man. Mutations in this gene cause a form of progressive familial intrahepatic cholestases which are a group of inherited disorders with severe cholestatic liver disease from early infancy. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a domain ABC transporter 2 (size 238) in uniprot entity ABCBB_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_003742.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ABCB11	NM_003742.4	c.3692G>T	p.Arg1231Leu	missense_variant	Exon 27 of 28	ENST00000650372.1	NP_003733.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ABCB11	ENST00000650372.1	c.3692G>T	p.Arg1231Leu	missense_variant	Exon 27 of 28		NM_003742.4	ENSP00000497931.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461582 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727086

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Progressive familial intrahepatic cholestasis type 2 Pathogenic:1

Feb 05, 2025

Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

The p.Arg1231Leu variant in ABCB11 has not been previously reported in the literature in individuals with BSEP deficiency, but has been identified in 0.00008% (1/1179716) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org). Although this variant has been seen in the general population in a heterozygous state, its frequency is low enough to be consistent with a recessive carrier frequency. Computational prediction tools and conservation analyses suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. Three additional pathogenic variants resulting in a different amino acid change at the same position, p.Arg1231Gln, p.Arg1231Gly, and p.Arg1231Trp, have been reported in association with disease in ClinVar, supporting that a change at this position may not be tolerated (Variation ID: 287364, 2751382, 973516). In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic for autosomal recessive BSEP deficiency. ACMG/AMP Criteria applied: PM5_strong, PP3_moderate, PM2_supporting (Richards 2015). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D;D;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	.;D;D
M_CAP	Pathogenic	0.76	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	M;M;.
PrimateAI	Uncertain	0.77	T
PROVEAN	Pathogenic	-6.6	D;.;.
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;.;.
Sift4G	Pathogenic	0.0	D;.;.
Polyphen		1.0	D;D;.
Vest4		0.97
MutPred		0.96		Loss of MoRF binding (P = 0.0055);Loss of MoRF binding (P = 0.0055);.;
MVP		0.94
MPC		0.71
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.98
gMVP		0.96

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-169781240;