rs143730802

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_018941.4(CLN8):​c.1A>G​(p.Met1?) variant causes a start lost change. The variant allele was found at a frequency of 0.00000991 in 1,614,086 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 Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

CLN8
NM_018941.4 start_lost

Scores

9
3
4

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 6.01

Publications

4 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: Pathogenic. The variant received 16 ACMG points.

PVS1
Start lost variant, next in-frame start position is after 13 pathogenic variants. Next in-frame start position is after 28 codons. Genomic position: 1771136. Lost 0.095 part of the original CDS.
PP5
Variant 8-1771055-A-G is Pathogenic according to our data. Variant chr8-1771055-A-G is described in ClinVar as [Pathogenic]. Clinvar id is 487522.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CLN8NM_018941.4 linkc.1A>G p.Met1? start_lost Exon 2 of 3 ENST00000331222.6 NP_061764.2 Q9UBY8A0A024QZ57

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CLN8ENST00000331222.6 linkc.1A>G p.Met1? start_lost Exon 2 of 3 1 NM_018941.4 ENSP00000328182.4 Q9UBY8
KBTBD11-OT1ENST00000635855.1 linkn.1A>G non_coding_transcript_exon_variant Exon 2 of 30 5 ENSP00000489726.1 A0A1B0GTJ5

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152104
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000388
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:
0.0000119
AC:
3
AN:
251470
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000889
AC:
13
AN:
1461864
Hom.:
0
Cov.:
32
AF XY:
0.00000550
AC XY:
4
AN XY:
727234
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:
53396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1112008
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000197
AC:
3
AN:
152222
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74418
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41548
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000389
AC:
2
AN:
5148
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000188
Hom.:
0
Bravo
AF:
0.00000378
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

not provided Pathogenic:1
Nov 02, 2024
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Initiation codon variant in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 30741402) -

Neuronal ceroid lipofuscinosis 8 Pathogenic:1
-
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.792C>G mutation. -

Neuronal ceroid lipofuscinosis Pathogenic:1
Aug 04, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant disrupts a region of the CLN8 protein in which other variant(s) (p.Arg24Gly) have been determined to be pathogenic (PMID: 10508524, 10861296, 15160397, 16828266). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. ClinVar contains an entry for this variant (Variation ID: 487522). Disruption of the initiator codon has been observed in individual(s) with clinical features of neuronal ceroid lipofuscinosis type 8 (PMID: 30741402, 31069529). This variant is not present in population databases (gnomAD no frequency). This sequence change affects the initiator methionine of the CLN8 mRNA. The next in-frame methionine is located at codon 28. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.43
CADD
Benign
17
DANN
Benign
0.96
DEOGEN2
Benign
0.11
.;T;T;T;T;.;T;.;.
Eigen
Uncertain
0.40
Eigen_PC
Uncertain
0.31
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D;.;.;.;.;D;.;D;D
M_CAP
Pathogenic
0.77
D
MetaRNN
Pathogenic
0.78
D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.93
D
PhyloP100
6.0
PROVEAN
Benign
0.31
.;N;.;.;.;.;.;.;.
REVEL
Pathogenic
0.67
Sift
Pathogenic
0.0
.;D;.;.;.;.;.;.;.
Sift4G
Pathogenic
0.0
D;D;.;.;.;.;.;D;.
Polyphen
1.0
.;D;D;D;D;.;D;.;.
Vest4
0.95
MVP
0.96
ClinPred
0.99
D
GERP RS
5.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.78
gMVP
0.69
Mutation Taster
=48/152
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: rs143730802; hg19: chr8-1719221; API