8-1771148-T-G

Position:

chr8-1771148-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The ENST00000331222.6(CLN8):c.94T>G(p.Phe32Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000539 in 1,614,070 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. F32L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000056 ( 0 hom. )

Consequence

CLN8
ENST00000331222.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 7.23

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 Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 10 uncertain in ENST00000331222.6

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.873

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLN8	NM_018941.4 linkuse as main transcript	c.94T>G	p.Phe32Val	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.94T>G	p.Phe32Val	missense_variant	2/3	1	NM_018941.4	ENSP00000328182	P1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152066

Hom.:

Cov.:

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:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251478

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.0000615

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:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000561

AC:

AN:

1461886

Hom.:

Cov.:

AF XY:

0.0000454

AC XY:

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:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000674

Gnomad4 OTH exome

AF:

0.0000993

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152184

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74412

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000564

Hom.:

Bravo

AF:

0.0000340

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.000119

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 14, 2023

The c.94T>G (p.F32V) alteration is located in exon 2 (coding exon 1) of the CLN8 gene. This alteration results from a T to G substitution at nucleotide position 94, causing the phenylalanine (F) at amino acid position 32 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

May 07, 2014

- -

Neuronal ceroid lipofuscinosis

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 22, 2022

This sequence change replaces phenylalanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 32 of the CLN8 protein (p.Phe32Val). This variant is present in population databases (rs758068226, gnomAD 0.004%). 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: 195346). 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 CLN8 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. -

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

Feb 24, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.36

BayesDel_addAF

Pathogenic

0.17

BayesDel_noAF

Pathogenic

0.19

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.65

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

Eigen

Uncertain

0.38

Eigen_PC

Uncertain

0.35

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Benign

0.81

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

M_CAP

Uncertain

0.21

MetaRNN

Pathogenic

0.87

D;D;D;D;D;D;D;D;D

MetaSVM

Uncertain

0.65

MutationAssessor

Uncertain

2.6

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

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.56

PROVEAN

Uncertain

-3.6

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

REVEL

Pathogenic

0.81

Sift

Benign

0.034

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

Sift4G

Uncertain

0.033

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

Polyphen

0.99

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

Vest4

0.75

MutPred

0.65

Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);Loss of helix (P = 0.079);

MVP

0.95

MPC

0.12

ClinPred

0.80

GERP RS

5.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.39

gMVP

0.76

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