chr8-1771527-A-C

Variant names:

• chr8-1771527-A-C
• rs386834130
• NM_018941.4:c.473A>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Moderate PP5_Moderate

The NM_018941.4(CLN8):​c.473A>C​(p.Tyr158Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,876 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 Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y158C) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CLN8 NM_018941.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.41
• Publications: 12 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: 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

KBTBD11-OT1 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 10 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, 8 uncertain in NM_018941.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr8-1771527-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 56710.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.898
• PP5: Variant 8-1771527-A-C is Pathogenic according to our data. Variant chr8-1771527-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 802387.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CLN8	NM_018941.4	c.473A>C	p.Tyr158Ser	missense_variant	Exon 2 of 3	ENST00000331222.6	NP_061764.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CLN8	ENST00000331222.6	c.473A>C	p.Tyr158Ser	missense_variant	Exon 2 of 3	1	NM_018941.4	ENSP00000328182.4
KBTBD11-OT1	ENST00000635855.1	n.473A>C		non_coding_transcript_exon_variant	Exon 2 of 30	5		ENSP00000489726.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461876 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727240

African (AFR) AF: 0.00 AC: 0 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: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronal ceroid lipofuscinosis Pathogenic:1

May 28, 2019

Mendelics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.67
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.070
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.85	D;D;D;D;.;D;.
Eigen	Uncertain	0.49
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Benign	0.84	.;.;.;.;T;.;T
M_CAP	Pathogenic	0.40	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D;D;D
MetaSVM	Uncertain	0.58	D
MutationAssessor	Uncertain	2.4	M;M;M;M;.;M;.
PhyloP100		6.4
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-4.9	D;.;.;.;.;.;.
REVEL	Pathogenic	0.77
Sift	Uncertain	0.0060	D;.;.;.;.;.;.
Sift4G	Uncertain	0.0020	D;.;.;.;.;.;D
Polyphen		1.0	D;D;D;D;.;D;.
Vest4		0.75
MutPred		0.63		Gain of helix (P = 0.0164);Gain of helix (P = 0.0164);Gain of helix (P = 0.0164);Gain of helix (P = 0.0164);Gain of helix (P = 0.0164);Gain of helix (P = 0.0164);Gain of helix (P = 0.0164);
MVP		0.95
MPC		0.32
ClinPred		0.98	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.48
gMVP		0.86
Mutation Taster		=33/67	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

Other links and lift over

dbSNP: rs386834130; hg19: chr8-1719693;