chr14-24428920-G-C

Position:

• chr14-24428920-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_001039771.3(CBLN3):​c.135C>G​(p.Cys45Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000142 in 1,412,050 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CBLN3 NM_001039771.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.99

Genes affected

CBLN3 (HGNC:20146): (cerebellin 3 precursor) Members of the precerebellin family, such as CBLN3, contain a cerebellin motif (see CBLN1; MIM 600432) and a C-terminal C1q signature domain (see MIM 120550) that mediates trimeric assembly of atypical collagen complexes. However, precerebellins do not contain a collagen motif, suggesting that they are not conventional components of the extracellular matrix (Pang et al., 2000 [PubMed 10964938]).[supplied by OMIM, Aug 2009]

KHNYN (HGNC:20166): (KH and NYN domain containing) The protein encoded by this gene contains a ribonuclease NYN domain and belongs to the N4BP1 family. The protein is a cofactor for the zinc finger antiviral protein (ZAP protein) which targets viral RNA for degradation and restricts SARS-CoV-2 infection. [provided by RefSeq, Sep 2021]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a disulfide_bond Interchain (size 0) in uniprot entity CBLN3_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.807

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CBLN3	NM_001039771.3	c.135C>G	p.Cys45Trp	missense_variant	1/3	ENST00000267406.11	NP_001034860.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CBLN3	ENST00000267406.11	c.135C>G	p.Cys45Trp	missense_variant	1/3	1	NM_001039771.3	ENSP00000267406.6
CBLN3	ENST00000555436.1	c.148-515C>G		intron_variant		3		ENSP00000450935.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000142 AC: 2 AN: 1412050 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 698296

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00000184

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 04, 2024

The c.135C>G (p.C45W) alteration is located in exon 1 (coding exon 1) of the CBLN3 gene. This alteration results from a C to G substitution at nucleotide position 135, causing the cysteine (C) at amino acid position 45 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.13
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.60	D
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.97	D
M_CAP	Uncertain	0.24	D
MetaRNN	Pathogenic	0.81	D
MetaSVM	Uncertain	0.076	D
MutationAssessor	Uncertain	2.2	M
PrimateAI	Pathogenic	0.91	D
PROVEAN	Uncertain	-3.6	D
REVEL	Uncertain	0.63
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.76
MutPred		0.50		Loss of catalytic residue at L46 (P = 0.0095);
MVP		0.93
MPC		1.2
ClinPred		0.99	D
GERP RS		2.4
Varity_R		0.83
gMVP		0.89

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: rs1594749849; hg19: chr14-24898126;