chr8-1771527-A-C

Position:

• chr8-1771527-A-C

Variant summary

Our verdict is Pathogenic. Variant got 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 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

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM1: In a domain TLC (size 200) in uniprot entity CLN8_HUMAN there are 17 pathogenic changes around while only 5 benign (77%) 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 Lovd as [Pathogenic].
• 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 id is 802387.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLN8	NM_018941.4	c.473A>C	p.Tyr158Ser	missense_variant	2/3	ENST00000331222.6	NP_061764.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLN8	ENST00000331222.6	c.473A>C	p.Tyr158Ser	missense_variant	2/3	1	NM_018941.4	ENSP00000328182	P1

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

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronal ceroid lipofuscinosis Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Mendelics

May 28, 2019

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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;.
MutationTaster	Benign	1.0	D
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

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

LitVar

Other links and lift over

dbSNP: rs386834130; hg19: chr8-1719693;