chr16-28477528-G-C

Position:

• chr16-28477528-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_001042432.2(CLN3):​c.1305C>G​(p.Cys435Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000411 in 1,461,192 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: CLN3 NM_001042432.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.35

Genes affected

CLN3 (HGNC:2074): (CLN3 lysosomal/endosomal transmembrane protein, battenin) This gene encodes a protein that is involved in lysosomal function. Mutations in this, as well as other neuronal ceroid-lipofuscinosis (CLN) genes, cause neurodegenerative diseases commonly known as Batten disease or collectively known as neuronal ceroid lipofuscinoses (NCLs). Many alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a lipid_moiety_binding_region S-farnesyl cysteine (size 0) in uniprot entity CLN3_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLN3	NM_001042432.2	c.1305C>G	p.Cys435Trp	missense_variant	16/16	ENST00000636147.2	NP_001035897.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLN3	ENST00000636147.2	c.1305C>G	p.Cys435Trp	missense_variant	16/16	1	NM_001042432.2	ENSP00000490105	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000239 AC: 6 AN: 251100 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135722

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000173

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1461192 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726880

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000134

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 18, 2017

The p.C435W variant (also known as c.1305C>G), located in coding exon 15 of the CLN3 gene, results from a C to G substitution at nucleotide position 1305. The cysteine at codon 435 is replaced by tryptophan, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

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 cysteine, which is neutral and slightly polar, with tryptophan, which is neutral and slightly polar, at codon 435 of the CLN3 protein (p.Cys435Trp). This variant is present in population databases (no rsID available, gnomAD 0.02%). This missense change has been observed in individual(s) with CLN3-related conditions (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 658557). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). 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	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.50
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.98	D;D;.;.;D;.;.;D;D;D;.;D;.;.
Eigen	Uncertain	0.41
Eigen_PC	Uncertain	0.24
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Uncertain	0.88	.;.;D;.;.;D;D;D;.;D;D;D;.;D
M_CAP	Pathogenic	0.78	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.9	H;H;.;.;.;.;.;.;H;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-9.7	.;D;.;.;D;D;D;.;D;.;D;.;.;D
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	.;D;.;.;D;D;D;.;D;.;D;.;.;D
Sift4G	Pathogenic	0.0	.;.;D;.;D;D;D;.;D;.;D;.;.;.
Polyphen		1.0	D;D;.;.;D;.;.;.;D;D;D;D;.;D
Vest4		0.72, 0.88, 0.86, 0.88, 0.87, 0.90
MutPred		0.93		Gain of catalytic residue at C435 (P = 0.0205);Gain of catalytic residue at C435 (P = 0.0205);.;.;.;.;.;.;Gain of catalytic residue at C435 (P = 0.0205);.;.;.;.;.;
MVP		0.97
MPC		0.74
ClinPred		1.0	D
GERP RS		0.77
Varity_R		0.97
gMVP		0.88

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: rs1216521924; hg19: chr16-28488849;