18-57688361-G-A

Position:

• chr18-57688361-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PP2 PP3_Strong PP5_Moderate

The NM_001374385.1(ATP8B1):​c.1367C>T​(p.Thr456Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. T456T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: ATP8B1 NM_001374385.1 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 10.0

Genes affected

ATP8B1 (HGNC:3706): (ATPase phospholipid transporting 8B1) This gene encodes a member of the P-type cation transport ATPase family, which belongs to the subfamily of aminophospholipid-transporting ATPases. The aminophospholipid translocases transport phosphatidylserine and phosphatidylethanolamine from one side of a bilayer to another. Mutations in this gene may result in progressive familial intrahepatic cholestasis type 1 and in benign recurrent intrahepatic cholestasis. [provided by RefSeq, Jul 2008]

(HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), ATP8B1. . Trascript score misZ 3.3227 (greater than threshold 3.09). GenCC has associacion of gene with progressive familial intrahepatic cholestasis type 1, cholestasis, intrahepatic, of pregnancy, 1.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.97
• PP5: Variant 18-57688361-G-A is Pathogenic according to our data. Variant chr18-57688361-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 7273.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ATP8B1	NM_001374385.1	c.1367C>T	p.Thr456Met	missense_variant	13/28	ENST00000648908.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ATP8B1	ENST00000648908.2	c.1367C>T	p.Thr456Met	missense_variant	13/28		NM_001374385.1	P1
	ENST00000588925.5	n.571-43053G>A		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461882 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727242

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000374

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Progressive familial intrahepatic cholestasis type 1 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Neuberg Centre For Genomic Medicine, NCGM	May 20, 2023	The observed missense c.1367C>T(p.Thr456Met) variant in ATP8B1 gene has been reported previously in homozygous and compound heterozygous states in multiple individuals affected with progressive familial intrahepatic cholestasis (Mínguez Rodríguez B, et al., 2022; Mizutani A, et al., 2020; Oya Y, et al., 2017; Alvarez L, et al., 2004). The p.Thr456Met variant is absent in gnomAD Exomes. This variant has been submitted to the ClinVar database as Pathogenic. Multiple lines of computational evidences (Polyphen - Probably damaging, SIFT - Damaging and MutationTaster - Disease causing) predict a damaging effect on protein structure and function for this variant. The reference amino acid is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. The amino acid Thr at position 456 is changed to a Met changing protein sequence and it might alter its composition and physico-chemical properties. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	literature only	OMIM	Oct 15, 2004	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.81	D;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Pathogenic	1.0	.;D
M_CAP	Pathogenic	0.29	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Uncertain	0.69	D
MutationAssessor	Pathogenic	4.3	H;H
MutationTaster	Benign	1.0	A;A
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-5.8	D;.
REVEL	Pathogenic	0.83
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0	D;.
Polyphen		1.0	D;D
Vest4		0.99
MutPred		0.86		Loss of methylation at K455 (P = 0.0444);Loss of methylation at K455 (P = 0.0444);
MVP		0.96
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.73
gMVP		0.95

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

LitVar

Other links and lift over

dbSNP: rs121909104; hg19: chr18-55355593; COSMIC: COSV52177697;