rs587779411

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PM2PP3PP5

The NM_018941.4(CLN8):​c.792C>G​(p.Asn264Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,614,120 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. N264N) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CLN8
NM_018941.4 missense

Scores

7
9
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:3

Conservation

PhyloP100: 1.06

Publications

6 publications found
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 Gene-Disease associations (from GenCC):
  • neuronal ceroid lipofuscinosis
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • neuronal ceroid lipofuscinosis 8
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P, Orphanet, Ambry Genetics, Myriad Women’s Health
  • neuronal ceroid lipofuscinosis 8 northern epilepsy variant
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
  • autism spectrum disorder
    Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 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 3 benign, 14 uncertain in NM_018941.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.822
PP5
Variant 8-1780498-C-G is Pathogenic according to our data. Variant chr8-1780498-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 100736.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CLN8NM_018941.4 linkc.792C>G p.Asn264Lys missense_variant Exon 3 of 3 ENST00000331222.6 NP_061764.2 Q9UBY8A0A024QZ57

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CLN8ENST00000331222.6 linkc.792C>G p.Asn264Lys missense_variant Exon 3 of 3 1 NM_018941.4 ENSP00000328182.4 Q9UBY8
KBTBD11-OT1ENST00000635855.1 linkn.543+8901C>G intron_variant Intron 2 of 29 5 ENSP00000489726.1 A0A1B0GTJ5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152228
Hom.:
0
Cov.:
33
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461892
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.513
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152228
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41468
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Neuronal ceroid lipofuscinosis 8 Pathogenic:2Uncertain:2
-
Unidad de Diagnostico y Tratamiento de Errores Congenitos del Metabolismo. Hospital Clínico Universitário de Santiago de Compostela
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Nov 17, 2021
Myriad Genetics, Inc.
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

NM_018941.3(CLN8):c.792C>G(N264K) is a missense variant classified as a variant of uncertain significance in the context of CLN8-related neuronal ceroid lipofuscinosis. N264K has been observed in cases with relevant disease (PMID: 30741402, 24767253). Functional assessments of this variant are not available in the literature. N264K has been observed in population frequency databases (gnomAD: NFE 0.01%). In summary, there is insufficient evidence to classify NM_018941.3(CLN8):c.792C>G(N264K) as pathogenic or benign. Please note: this variant was assessed in the context of healthy population screening. -

May 22, 2022
3billion
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.003%). In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.91; 3Cnet: 0.74). Same nucleotide change resulting in same amino acid change has been previously reported to be associated with CLN8 related disorder (ClinVar ID: VCV000100736 / PMID: 24767253, 30741402). However, the evidence of pathogenicity is insufficient at this time. Therefore, this variant is classified as uncertain significanceaccording to the recommendation of ACMG/AMP guideline. -

-
Translational Research Program on Neuronal Ceroid Lipofuscinosis, Center for the Study of Inborn Errors of Metabolism
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

This mutation was detected in heterozygous state, combined with a c.1A>G mutation. -

Neuronal ceroid lipofuscinosis Pathogenic:1Uncertain:1
May 28, 2019
Mendelics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces asparagine, which is neutral and polar, with lysine, which is basic and polar, at codon 264 of the CLN8 protein (p.Asn264Lys). This variant is present in population databases (rs587779411, gnomAD 0.007%). This missense change has been observed in individual(s) with CLN8-related conditions (PMID: 24767253, 30741402). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 100736). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. 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 Pathogenic:1
Jun 17, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Uncertain
0.0
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.44
T;T;T;T;T
Eigen
Uncertain
0.33
Eigen_PC
Uncertain
0.28
FATHMM_MKL
Uncertain
0.91
D
M_CAP
Pathogenic
0.34
D
MetaRNN
Pathogenic
0.82
D;D;D;D;D
MetaSVM
Uncertain
0.71
D
MutationAssessor
Uncertain
2.3
M;M;M;M;M
PhyloP100
1.1
PrimateAI
Uncertain
0.62
T
PROVEAN
Benign
-2.0
N;.;.;.;.
REVEL
Pathogenic
0.91
Sift
Pathogenic
0.0
D;.;.;.;.
Sift4G
Pathogenic
0.0
D;.;.;.;.
Polyphen
0.99
D;D;D;D;D
Vest4
0.69
MutPred
0.71
Gain of methylation at N264 (P = 1e-04);Gain of methylation at N264 (P = 1e-04);Gain of methylation at N264 (P = 1e-04);Gain of methylation at N264 (P = 1e-04);Gain of methylation at N264 (P = 1e-04);
MVP
0.96
MPC
0.30
ClinPred
0.96
D
GERP RS
3.4
Varity_R
0.42
gMVP
0.90
Mutation Taster
=20/80
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs587779411; hg19: chr8-1728664; API