8-1771055-A-T

Variant names:

• chr8-1771055-A-T
• rs143730802
• NM_018941.4:c.1A>T

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PVS1 PS1_Moderate PM2 PP5_Moderate

The NM_018941.4(CLN8):​c.1A>T​(p.Met1?) variant causes a initiator codon change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CLN8 NM_018941.4 initiator_codon
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.01
• Publications: 0 publications found

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: Genomics England PanelApp, Orphanet, Myriad Women’s Health, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• 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

KBTBD11-OT1 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 14 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.
• PS1: Another start lost variant in NM_018941.4 (CLN8) was described as [Likely_pathogenic] in ClinVar
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-1771055-A-T is Pathogenic according to our data. Variant chr8-1771055-A-T is described in ClinVar as Pathogenic. ClinVar VariationId is 2749928.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_018941.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CLN8	NM_018941.4	MANE Select	c.1A>T	p.Met1?	initiator_codon	Exon 2 of 3	NP_061764.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CLN8	ENST00000331222.6	TSL:1 MANE Select	c.1A>T	p.Met1?	initiator_codon	Exon 2 of 3	ENSP00000328182.4	Q9UBY8
	KBTBD11-OT1	ENST00000635855.1	TSL:5	n.1A>T		non_coding_transcript_exon	Exon 2 of 30	ENSP00000489726.1	A0A1B0GTJ5
	CLN8	ENST00000519254.2	TSL:5	c.1A>T	p.Met1?	initiator_codon	Exon 2 of 3	ENSP00000490016.1	Q9UBY8

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Neuronal ceroid lipofuscinosis (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Benign	18
DANN	Benign	0.84
DEOGEN2	Benign	0.11	T
Eigen	Uncertain	0.40
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.73	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.87	D
PhyloP100		6.0
PROVEAN	Benign	0.010	N
REVEL	Pathogenic	0.68
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.99	D
Vest4		0.93
MutPred		0.99		Loss of phosphorylation at S5 (P = 0.2097)
MVP		0.96
ClinPred		0.97	D
GERP RS		5.2
Varity_R		0.82
gMVP		0.60
Mutation Taster		=48/152	disease causing

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

Other links and lift over

dbSNP: rs143730802; hg19: chr8-1719221;