rs138216814

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_001253852.3(AP4B1):c.670C>T(p.Arg224Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000041 in 1,611,040 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R224H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000042 ( 0 hom. )

Consequence

AP4B1
NM_001253852.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 9.62

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 Uncertain_significance. Variant got 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.835

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AP4B1	NM_001253852.3 linkuse as main transcript	c.670C>T	p.Arg224Cys	missense_variant	5/10	ENST00000369569.6
AP4B1-AS1	NR_125965.1 linkuse as main transcript	n.1013G>A		non_coding_transcript_exon_variant	5/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AP4B1	ENST00000369569.6 linkuse as main transcript	c.670C>T	p.Arg224Cys	missense_variant	5/10	1	NM_001253852.3	P1	Q9Y6B7-1
AP4B1-AS1	ENST00000419536.1 linkuse as main transcript	n.845G>A		non_coding_transcript_exon_variant	5/5	2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152136

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000192

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000485

AC:

AN:

247234

Hom.:

AF XY:

0.0000448

AC XY:

AN XY:

133810

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000903

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000279

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000465

Gnomad NFE exome

AF:

0.0000267

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000425

AC:

AN:

1458904

Hom.:

Cov.:

AF XY:

0.0000468

AC XY:

AN XY:

725804

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000917

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000882

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.0000198

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152136

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74322

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000192

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.0000658

Hom.:

Bravo

AF:

0.0000302

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000412

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 47

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 11, 2023	This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 224 of the AP4B1 protein (p.Arg224Cys). This variant is present in population databases (rs138216814, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with AP4B1-related conditions. ClinVar contains an entry for this variant (Variation ID: 210196). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt AP4B1 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Oct 20, 2014

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.25

BayesDel_addAF

Uncertain

0.062

BayesDel_noAF

Pathogenic

0.15

Cadd

Pathogenic

Dann

Pathogenic

1.0

DEOGEN2

Benign

0.34

T;T;T;T;T;T

Eigen

Pathogenic

0.92

Eigen_PC

Pathogenic

0.88

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.96

D;.;D;D;D;D

M_CAP

Benign

0.082

MetaRNN

Pathogenic

0.83

D;D;D;D;D;D

MetaSVM

Benign

-0.69

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Uncertain

0.69

PROVEAN

Pathogenic

-5.9

D;D;D;D;D;D

REVEL

Pathogenic

0.72

Sift

Pathogenic

0.0

D;D;D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;.;.;.

Polyphen

1.0

D;D;D;.;.;.

Vest4

0.92

MVP

0.72

MPC

0.67

ClinPred

0.83

GERP RS

5.2

Varity_R

0.88

gMVP

0.54

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