rs374894037

Variant summary

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

The NM_001253852.3(AP4B1):c.1177C>T(p.Arg393Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000621 in 1,609,488 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. R393R) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

AP4B1
NM_001253852.3 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 3.09

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 1-113898739-G-A is Pathogenic according to our data. Variant chr1-113898739-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 539527.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AP4B1	NM_001253852.3 linkuse as main transcript	c.1177C>T	p.Arg393Ter	stop_gained	6/10	ENST00000369569.6
AP4B1-AS1	NR_125965.1 linkuse as main transcript	n.536+750G>A		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AP4B1	ENST00000369569.6 linkuse as main transcript	c.1177C>T	p.Arg393Ter	stop_gained	6/10	1	NM_001253852.3	P1	Q9Y6B7-1
AP4B1-AS1	ENST00000419536.1 linkuse as main transcript	n.368+750G>A		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes

AF:

0.0000395

AC:

AN:

151968

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000725

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.000479

GnomAD3 exomes

AF:

0.00000405

AC:

AN:

247150

Hom.:

AF XY:

0.00

AC XY:

AN XY:

133902

show subpopulations

Gnomad AFR exome

AF:

0.0000617

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1457520

Hom.:

Cov.:

AF XY:

0.00000414

AC XY:

AN XY:

725260

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000395

AC:

AN:

151968

Hom.:

Cov.:

AF XY:

0.0000404

AC XY:

AN XY:

74222

show subpopulations

Gnomad4 AFR

AF:

0.0000725

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.000479

Alfa

AF:

0.0000417

Hom.:

Bravo

AF:

0.0000340

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 47

Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	DASA	Nov 03, 2022	The c.1177C>T;p.(Arg393*) variant creates a premature translational stop signal in the AP4B1 gene. It is expected to result in an absent or disrupted protein product - PVS1. ClinVar contains an entry for this variant (ClinVar ID: 539527) - PS4_supporting. The variant is present at low allele frequencies population databases (rs374894037 – gnomAD 0.0003948%; ABraOM 0.000427 frequency - https://abraom.ib.usp.br/) - PM2_supporting. In summary, the currently available evidence indicates that the variant is pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Apr 16, 2023	The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change creates a premature translational stop signal (p.Arg393*) 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 premature translational stop signal has been observed in individuals with hereditary spastic paraplegia (PMID: 32979048). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 539527). -
Pathogenic, criteria provided, single submitter	research	HudsonAlpha Institute for Biotechnology, HudsonAlpha Institute for Biotechnology	Oct 11, 2019	- -
Pathogenic, criteria provided, single submitter	clinical testing	Paris Brain Institute, Inserm - ICM	-	- -

Spastic paraplegia

Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Yale Center for Mendelian Genomics, Yale University

Oct 01, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.43

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Pathogenic

0.93

Eigen_PC

Pathogenic

0.78

FATHMM_MKL

Uncertain

0.91

MutationTaster

Benign

1.0

A;A;A

Vest4

0.41

GERP RS

4.5

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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