rs776976178

Variant summary

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

The NM_001253852.3(AP4B1):​c.1216C>T​(p.Arg406*) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000229 in 1,613,954 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

AP4B1
NM_001253852.3 stop_gained

Scores

5
1
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 5.92
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-AS1 (HGNC:44114): (AP4B1 antisense RNA 1)

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 1-113897926-G-A is Pathogenic according to our data. Variant chr1-113897926-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 422147.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
AP4B1NM_001253852.3 linkc.1216C>T p.Arg406* stop_gained Exon 7 of 10 ENST00000369569.6 NP_001240781.1 Q9Y6B7-1A0A024R0J5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
AP4B1ENST00000369569.6 linkc.1216C>T p.Arg406* stop_gained Exon 7 of 10 1 NM_001253852.3 ENSP00000358582.1 Q9Y6B7-1

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152070
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000557
AC:
14
AN:
251462
Hom.:
0
AF XY:
0.0000809
AC XY:
11
AN XY:
135906
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000980
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000967
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000239
AC:
35
AN:
1461884
Hom.:
0
Cov.:
31
AF XY:
0.0000316
AC XY:
23
AN XY:
727244
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000216
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152070
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74274
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000413
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.000115
AC:
14
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 47 Pathogenic:4
Jan 04, 2017
Molecular Genetics Laboratory, BC Children's and BC Women's Hospitals
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Apr 11, 2023
Genome-Nilou Lab
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jul 07, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This premature translational stop signal has been observed in individuals with hereditary spastic paraplegia (PMID: 29193663). This sequence change creates a premature translational stop signal (p.Arg406*) 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 (rs776976178, gnomAD 0.01%). ClinVar contains an entry for this variant (Variation ID: 422147). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

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 (14 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, 33594065). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

not provided Pathogenic:2
Apr 26, 2020
Genetics and Genomic Medicine Centre, NeuroGen Healthcare, NeuroGen Healthcare
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 28, 2023
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Nonsense 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; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 35379322, 33594065, 34426522, 35599849, 33294911, 31915823, 31525725, 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

- -

Hereditary spastic paraplegia Pathogenic:1
Jan 31, 2017
Genome Diagnostics Laboratory, The Hospital for Sick Children
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.48
D
BayesDel_noAF
Pathogenic
0.63
CADD
Pathogenic
45
DANN
Uncertain
1.0
Eigen
Pathogenic
0.96
Eigen_PC
Pathogenic
0.84
FATHMM_MKL
Pathogenic
0.98
D
Vest4
0.47
GERP RS
5.5

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.20
Details are displayed if max score is > 0.2
DS_AL_spliceai
0.20
Position offset: 17

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.

Other links and lift over

dbSNP: rs776976178; hg19: chr1-114440548; API