8-1780512-A-G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM1BP4_Strong

The NM_018941.4(CLN8):​c.806A>G​(p.Glu269Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,614,126 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign 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. E269V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CLN8
NM_018941.4 missense

Scores

18

Clinical Significance

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

Conservation

PhyloP100: 1.04

Publications

8 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_benign. The variant received -2 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 10 uncertain in NM_018941.4
BP4
Computational evidence support a benign effect (MetaRNN=0.053525448).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CLN8NM_018941.4 linkc.806A>G p.Glu269Gly 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.806A>G p.Glu269Gly missense_variant Exon 3 of 3 1 NM_018941.4 ENSP00000328182.4 Q9UBY8
KBTBD11-OT1ENST00000635855.1 linkn.543+8915A>G intron_variant Intron 2 of 29 5 ENSP00000489726.1 A0A1B0GTJ5

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152236
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000482
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251112
AF XY:
0.00000737
show subpopulations
Gnomad AFR exome
AF:
0.000246
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
0.00000274
AC:
4
AN:
1461890
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
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:
0.00
AC:
0
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
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:
0.0000131
AC:
2
AN:
152236
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74368
show subpopulations
African (AFR)
AF:
0.0000482
AC:
2
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:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68050
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
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
Bravo
AF:
0.0000378
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:1
Dec 03, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Neuronal ceroid lipofuscinosis 8 Uncertain:1
Oct 28, 2019
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Neuronal ceroid lipofuscinosis Uncertain:1
Jul 31, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 269 of the CLN8 protein (p.Glu269Gly). This variant is present in population databases (rs139003032, 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: 205197). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". 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
0.089
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.36
CADD
Benign
13
DANN
Benign
0.97
DEOGEN2
Benign
0.17
T;T;T;T;T
Eigen
Benign
-1.1
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.023
N
M_CAP
Benign
0.063
D
MetaRNN
Benign
0.054
T;T;T;T;T
MetaSVM
Benign
-0.61
T
MutationAssessor
Benign
1.2
L;L;L;L;L
PhyloP100
1.0
PrimateAI
Benign
0.31
T
PROVEAN
Benign
-0.39
N;.;.;.;.
REVEL
Benign
0.15
Sift
Benign
0.21
T;.;.;.;.
Sift4G
Benign
0.36
T;.;.;.;.
Polyphen
0.0
B;B;B;B;B
Vest4
0.064
MutPred
0.20
Loss of loop (P = 0.0073);Loss of loop (P = 0.0073);Loss of loop (P = 0.0073);Loss of loop (P = 0.0073);Loss of loop (P = 0.0073);
MVP
0.83
MPC
0.043
ClinPred
0.017
T
GERP RS
-2.5
Varity_R
0.031
gMVP
0.48
Mutation Taster
=94/6
polymorphism

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: rs139003032; hg19: chr8-1728678; API