rs112062713

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBS1_Supporting

The NM_001174150.2(ARL13B):c.1261A>G(p.Ser421Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000607 in 1,613,348 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00034 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000032 ( 0 hom. )

Consequence

ARL13B
NM_001174150.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.53

Variant links:

Genes affected

ARL13B (HGNC:25419): (ADP ribosylation factor like GTPase 13B) This gene encodes a member of the ADP-ribosylation factor-like family. The encoded protein is a small GTPase that contains both N-terminal and C-terminal guanine nucleotide-binding motifs. This protein is localized in the cilia and plays a role in cilia formation and in maintenance of cilia. Mutations in this gene are the cause of Joubert syndrome 8. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Mar 2010]

ARL13B links:

DHFR2 (HGNC:27309): (dihydrofolate reductase 2) Enables dihydrofolate reductase activity and mRNA binding activity. Involved in tetrahydrofolate metabolic process and thymidine biosynthetic process. Located in mitochondrial inner membrane and mitochondrial matrix. [provided by Alliance of Genome Resources, Apr 2022]

DHFR2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.026384115).

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000335 (51/152188) while in subpopulation AFR AF= 0.00118 (49/41456). AF 95% confidence interval is 0.000919. There are 0 homozygotes in gnomad4. There are 24 alleles in male gnomad4 subpopulation. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ARL13B	NM_001174150.2 linkuse as main transcript	c.1261A>G	p.Ser421Gly	missense_variant	10/10	ENST00000394222.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ARL13B	ENST00000394222.8 linkuse as main transcript	c.1261A>G	p.Ser421Gly	missense_variant	10/10	1	NM_001174150.2	P1	Q3SXY8-1

Frequencies

GnomAD3 genomes

AF:

0.000335

AC:

AN:

152188

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00118

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.000478

GnomAD3 exomes

AF:

0.0000717

AC:

AN:

251008

Hom.:

AF XY:

0.0000442

AC XY:

AN XY:

135708

show subpopulations

Gnomad AFR exome

AF:

0.00111

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:

0.0000322

AC:

AN:

1461160

Hom.:

Cov.:

AF XY:

0.0000220

AC XY:

AN XY:

726906

show subpopulations

Gnomad4 AFR exome

AF:

0.00120

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.000116

GnomAD4 genome

AF:

0.000335

AC:

AN:

152188

Hom.:

Cov.:

AF XY:

0.000323

AC XY:

AN XY:

74338

show subpopulations

Gnomad4 AFR

AF:

0.00118

Gnomad4 AMR

AF:

0.00

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:

0.000478

Alfa

AF:

0.0000474

Hom.:

Bravo

AF:

0.000427

ESP6500AA

AF:

0.00159

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000824

AC:

Asia WGS

AF:

0.000866

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Joubert syndrome 8

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 19, 2022

This sequence change replaces serine, which is neutral and polar, with glycine, which is neutral and non-polar, at codon 421 of the ARL13B protein (p.Ser421Gly). This variant is present in population databases (rs112062713, gnomAD 0.1%). This variant has not been reported in the literature in individuals affected with ARL13B-related conditions. ClinVar contains an entry for this variant (Variation ID: 405194). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The glycine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.055

BayesDel_addAF

Benign

-0.52

BayesDel_noAF

Benign

-0.56

Cadd

Benign

8.4

Dann

Benign

0.54

Eigen

Benign

-0.99

Eigen_PC

Benign

-0.86

FATHMM_MKL

Benign

0.63

LIST_S2

Benign

0.68

T;T;.;T

M_CAP

Benign

0.017

MetaRNN

Benign

0.026

T;T;T;T

MetaSVM

Benign

-1.0

MutationTaster

Benign

0.93

N;N;N;N;N

PrimateAI

Benign

0.31

PROVEAN

Benign

-1.0

N;N;N;N

REVEL

Benign

0.11

Sift

Benign

0.34

T;T;T;T

Sift4G

Benign

0.69

T;T;T;T

Polyphen

0.0010, 0.0

.;B;B;B

Vest4

0.094

MVP

0.37

MPC

0.068

ClinPred

0.024

GERP RS

1.1

Varity_R

0.054

gMVP

0.22

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.030

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