15-68208358-C-T

Position:

chr15-68208358-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_017882.3(CLN6):c.718G>A(p.Ala240Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000868 in 1,613,780 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

CLN6
NM_017882.3 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 3.87

Variant links:

Genes affected

CLN6 (HGNC:2077): (CLN6 transmembrane ER protein) This gene is one of eight which have been associated with neuronal ceroid lipofuscinoses (NCL). Also referred to as Batten disease, NCL comprises a class of autosomal recessive, neurodegenerative disorders affecting children. The genes responsible likely encode proteins involved in the degradation of post-translationally modified proteins in lysosomes. The primary defect in NCL disorders is thought to be associated with lysosomal storage function. [provided by RefSeq, Oct 2008]

CLN6 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLN6	NM_017882.3 linkuse as main transcript	c.718G>A	p.Ala240Thr	missense_variant	7/7	ENST00000249806.11	NP_060352.1
CLN6	NM_001411068.1 linkuse as main transcript	c.814G>A	p.Ala272Thr	missense_variant	7/7		NP_001397997.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLN6	ENST00000249806.11 linkuse as main transcript	c.718G>A	p.Ala240Thr	missense_variant	7/7	1	NM_017882.3	ENSP00000249806	P1	Q9NWW5-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152184

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000120

AC:

AN:

251024

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135788

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000882

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000889

AC:

AN:

1461596

Hom.:

Cov.:

AF XY:

0.00000825

AC XY:

AN XY:

727096

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000540

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152184

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 29, 2018

The p.A240T variant (also known as c.718G>A), located in coding exon 7 of the CLN6 gene, results from a G to A substitution at nucleotide position 718. The alanine at codon 240 is replaced by threonine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Dec 23, 2015

A variant of uncertain significance has been identified in the CLN6 gene. The A240T variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The A240T variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size, and/or other properties. This substitution occurs at a position that is conserved in mammals and is predicted to be within the sixth transmembrane domain of the CLN6 protein (Kousi et al., 2012); however, Threonine is observed at this position in evolution. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Neuronal ceroid lipofuscinosis

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 25, 2022

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 240 of the CLN6 protein (p.Ala240Thr). This variant is present in population databases (rs779105796, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with CLN6-related conditions. ClinVar contains an entry for this variant (Variation ID: 420280). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CLN6 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

0.18

BayesDel_addAF

Uncertain

0.13

BayesDel_noAF

Uncertain

0.12

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.84

D;D;D;.;T;T

Eigen

Benign

-0.025

Eigen_PC

Benign

0.096

FATHMM_MKL

Uncertain

0.88

LIST_S2

Uncertain

0.87

D;D;D;D;D;D

M_CAP

Uncertain

0.15

MetaRNN

Uncertain

0.52

D;D;D;D;D;D

MetaSVM

Uncertain

0.37

MutationAssessor

Benign

1.6

L;.;.;.;.;.

MutationTaster

Benign

1.0

D;D;D;D;D;D

PrimateAI

Uncertain

0.62

PROVEAN

Benign

-2.2

N;D;N;N;.;.

REVEL

Pathogenic

0.66

Sift

Benign

0.18

T;T;T;T;.;.

Sift4G

Benign

0.13

T;D;D;T;.;.

Polyphen

0.13

B;.;.;.;.;.

Vest4

0.44

MutPred

0.50

.;.;.;Loss of catalytic residue at A272 (P = 0.1976);.;.;

MVP

0.93

MPC

0.30

ClinPred

0.47

GERP RS

4.4

Varity_R

0.17

gMVP

0.76

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over