dbSNP rs587779388: AP4B1:p.Thr387ArgfsTer30 (chr1-113898754-CTG-C) – ACMG Classification: Pathogenic (18 pts)

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001253852.3(AP4B1):c.1160_1161delCA(p.Thr387ArgfsTer30) variant causes a frameshift change. The variant allele was found at a frequency of 0.000111 in 1,609,850 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

AP4B1
NM_001253852.3 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:17B:1

Conservation

PhyloP100: 6.69

Variant links:

Genes affected

AP4B1 (HGNC:572): (adaptor related protein complex 4 subunit beta 1) This gene encodes a subunit of a heterotetrameric adapter-like complex 4 that is involved in targeting proteins from the trans-Golgi network to the endosomal-lysosomal system. Mutations in this gene are associated with cerebral palsy spastic quadriplegic type 5 (CPSQ5) disorder. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

AP4B1 links:

AP4B1-AS1 (HGNC:44114): (AP4B1 antisense RNA 1)

AP4B1-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 1-113898754-CTG-C is Pathogenic according to our data. Variant chr1-113898754-CTG-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 156414.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-113898754-CTG-C is described in Lovd as [Pathogenic]. Variant chr1-113898754-CTG-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
AP4B1	NM_001253852.3 link	c.1160_1161delCA	p.Thr387ArgfsTer30	frameshift_variant	Exon 6 of 10	ENST00000369569.6	NP_001240781.1	Q9Y6B7-1A0A024R0J5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AP4B1	ENST00000369569.6 link	c.1160_1161delCA	p.Thr387ArgfsTer30	frameshift_variant	Exon 6 of 10	1	NM_001253852.3	ENSP00000358582.1		Q9Y6B7-1

Frequencies

GnomAD3 genomes

AF:

0.000138

AC:

AN:

152144

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00173

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.000189

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000191

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000137

AC:

AN:

247490

Hom.:

AF XY:

0.000142

AC XY:

AN XY:

134086

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.000695

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000238

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000108

AC:

157

AN:

1457706

Hom.:

AF XY:

0.000127

AC XY:

AN XY:

725356

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.000612

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000203

Gnomad4 NFE exome

AF:

0.000124

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.000138

AC:

AN:

152144

Hom.:

Cov.:

AF XY:

0.000175

AC XY:

AN XY:

74346

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00173

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000189

Gnomad4 NFE

AF:

0.000191

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000727

Hom.:

Bravo

AF:

0.0000907

EpiCase

AF:

0.000164

EpiControl

AF:

0.000178

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:17Benign:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 47

Pathogenic:9

Dec 04, 2024

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Criteria applied: PVS1,PM3_STR,PM2_SUP -

Apr 11, 2023

Genome-Nilou Lab

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 03, 2022

MGZ Medical Genetics Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 02, 2022

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with spastic paraplegia 47 (MIM#614066). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (37 heterozygotes, 0 homozygotes). (SP) 0701 - Many NMD predicted variants comparable to the one identified in this case have very strong previous evidence for pathogenicity (ClinVar). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been reported in multiple individuals with spastic paraplegia 47 (ClinVar, PMID: 29193663). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Jan 01, 2012

Institute of Human Genetics, University Medical Center Hamburg-Eppendorf

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

In two siblings who presented with severe ID, absent speech, microcephaly, growth retardation, and progressive spastic tetraplegia we detected the novel homozygous 2 bp deletion c.1159_1160delCA in AP4B1; the mutation was present in the heterozygous state in both parents. The AP4B1-associated phenotype has previously been assigned to spastic paraplegia-47 (SPG47). -

Apr 30, 2014

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Sep 04, 2019

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PVS1,PM2,PM3,PP5. This variant was detected in homozygous state. -

Nov 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Thr387Argfs*30) in the AP4B1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in AP4B1 are known to be pathogenic (PMID: 22290197, 24700674, 24781758). This variant is present in population databases (rs587779388, gnomAD 0.07%). This premature translational stop signal has been observed in individual(s) with AP4B1-related conditions (PMID: 24781758). ClinVar contains an entry for this variant (Variation ID: 156414). For these reasons, this variant has been classified as Pathogenic. -

Paris Brain Institute, Inserm - ICM

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Pathogenic:5

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Jan 28, 2021

Genetic Services Laboratory, University of Chicago

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Apr 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

AP4B1: PVS1, PM3:Strong, PM2 -

Nov 10, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Observed in homozygous state in several unrelated patients in published literature with hypotonia, spastic paraplegia, microcephaly, severe intellectual disability, and global developmental delay and not observed in homozygous state in controls (PMID: 32166732, 24781758); Reported with a second AP4B1 variant in an individual with SPG47 in the published literature (PMID: 29193663); Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 24781758, 21620353, 21440262, 22290197, 25552650, 25693842, 24700674, 19559397, 23167973, 20972249, 23472171, 31525725, 32166732, 31915823, 33728854, 32895917, 32964447, 33726816, 34544818, 34729478, 29193663) -

Spastic paraplegia

Pathogenic:1

Oct 01, 2020

Yale Center for Mendelian Genomics, Yale University

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Inborn genetic diseases

Pathogenic:1

Nov 30, 2016

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Abnormality of the nervous system

Pathogenic:1

Jul 10, 2021

Kariminejad - Najmabadi Pathology & Genetics Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Intellectual disability

Benign:1

Jan 01, 2019

Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over