chr8-1771113-C-G

Position:

chr8-1771113-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1PM2BP4

The NM_018941.4(CLN8):c.59C>G(p.Ser20Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000496 in 1,613,890 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000099 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

CLN8
NM_018941.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 2.67

Variant links:

Genes affected

CLN8 (HGNC:2079): (CLN8 transmembrane ER and ERGIC protein) This gene encodes a transmembrane protein belonging to a family of proteins containing TLC domains, which are postulated to function in lipid synthesis, transport, or sensing. The protein localizes to the endoplasmic reticulum (ER), and may recycle between the ER and ER-Golgi intermediate compartment. Mutations in this gene are associated with a disorder characterized by progressive epilepsy with cognitive disabilities (EPMR), which is a subtype of neuronal ceroid lipofuscinoses (NCL). Patients with mutations in this gene have altered levels of sphingolipid and phospholipids in the brain. [provided by RefSeq, Jul 2017]

CLN8 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM1

In a chain Protein CLN8 (size 285) in uniprot entity CLN8_HUMAN there are 20 pathogenic changes around while only 7 benign (74%) in NM_018941.4

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.37701562).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLN8	NM_018941.4 linkuse as main transcript	c.59C>G	p.Ser20Cys	missense_variant	2/3	ENST00000331222.6	NP_061764.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLN8	ENST00000331222.6 linkuse as main transcript	c.59C>G	p.Ser20Cys	missense_variant	2/3	1	NM_018941.4	ENSP00000328182	P1

Frequencies

GnomAD3 genomes

AF:

0.0000987

AC:

AN:

152002

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000459

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:

0.000118

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000596

AC:

AN:

251492

Hom.:

AF XY:

0.0000368

AC XY:

AN XY:

135922

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000289

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:

0.0000439

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000445

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.0000330

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000291

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:

0.0000441

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.0000987

AC:

AN:

152002

Hom.:

Cov.:

AF XY:

0.000121

AC XY:

AN XY:

74220

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000459

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000118

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000690

Hom.:

Bravo

AF:

0.000102

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.0000741

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000237

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 20, 2022	This sequence change replaces serine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 20 of the CLN8 protein (p.Ser20Cys). This variant is present in population databases (rs749651452, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with CLN8-related conditions. ClinVar contains an entry for this variant (Variation ID: 205203). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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, no assertion criteria provided	clinical testing	Natera, Inc.	Jan 17, 2020	- -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 23, 2016

The p.S20C variant (also known as c.59C>G), located in coding exon 1 of the CLN8 gene, results from a C to G substitution at nucleotide position 59. The serine at codon 20 is replaced by cysteine, an amino acid with dissimilar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Oct 24, 2023

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Intellectual disability

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille

Jan 01, 2019

- -

Neuronal ceroid lipofuscinosis 8;C1864923:Neuronal ceroid lipofuscinosis 8 northern epilepsy variant

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Jul 25, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.16

BayesDel_addAF

Benign

-0.057

BayesDel_noAF

Uncertain

-0.020

CADD

Benign

DANN

Uncertain

0.98

DEOGEN2

Benign

0.37

.;T;T;T;T;.;T;.;.

Eigen

Uncertain

0.24

Eigen_PC

Benign

0.12

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.80

T;.;.;.;.;T;.;T;T

M_CAP

Uncertain

0.25

MetaRNN

Benign

0.38

T;T;T;T;T;T;T;T;T

MetaSVM

Uncertain

0.69

MutationAssessor

Uncertain

2.5

.;M;M;M;M;.;M;.;.

MutationTaster

Benign

0.97

PrimateAI

Benign

0.43

PROVEAN

Benign

-1.5

.;N;.;.;.;.;.;.;.

REVEL

Uncertain

0.56

Sift

Benign

0.044

.;D;.;.;.;.;.;.;.

Sift4G

Uncertain

0.017

D;D;.;.;.;.;.;D;.

Polyphen

1.0

.;D;D;D;D;.;D;.;.

Vest4

0.49

MutPred

0.51

Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);Loss of phosphorylation at Y18 (P = 0.1082);

MVP

0.92

MPC

0.23

ClinPred

0.20

GERP RS

4.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.074

gMVP

0.70

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