11-119339419-A-G

Variant names:

• chr11-119339419-A-G
• rs779732274
• NM_001278431.2:c.644T>C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 3P and 3B. PM1 PP2 BP4_Moderate BS2_Supporting

The NM_001278431.2(C1QTNF5):​c.644T>C​(p.Ile215Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,613,442 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: C1QTNF5 NM_001278431.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 0.503
• Publications: 1 publications found

Genes affected

C1QTNF5 (HGNC:14344): (C1q and TNF related 5) This gene encodes a member of a family of proteins that function as components of basement membranes and may play a role in cell adhesion. Mutations in this gene have been associated with late-onset retinal degeneration. The protein may be encoded by either a bicistronic transcript including sequence from the upstream membrane frizzled-related protein gene (MFRP), or by a monocistronic transcript expressed from an internal promoter. [provided by RefSeq, Jun 2013]

MFRP (HGNC:18121): (membrane frizzled-related protein) This gene encodes a member of the frizzled-related protein family. The encoded protein plays an important role in eye development and mutations in this gene have been associated with nanophthalmos, posterior microphthalmia, retinitis pigmentosa, foveoschisis, and optic disc drusen. The protein is encoded by a bicistronic transcript which also encodes C1q and tumor necrosis factor related protein 5 (C1QTNF5). [provided by RefSeq, Jun 2013]

MFRP Gene-Disease associations (from GenCC):

• isolated microphthalmia 5

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia, G2P, Orphanet
• nanophthalmos 2

  Inheritance: AR Classification: DEFINITIVE, MODERATE Submitted by: Ambry Genetics, G2P
• nanophthalmia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM1: In a domain C1q (size 139) in uniprot entity C1QT5_HUMAN there are 7 pathogenic changes around while only 2 benign (78%) in NM_001278431.2
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 6 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Trascript score misZ: 0.7257 (below the threshold of 3.09). GenCC associations: The gene is linked to late-onset retinal degeneration.
• BP4: Computational evidence support a benign effect (MetaRNN=0.1824063).
• BS2: High AC in GnomAdExome4 at 9 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
C1QTNF5	NM_001278431.2	c.644T>C	p.Ile215Thr	missense_variant	Exon 3 of 3	ENST00000528368.3	NP_001265360.1
MFRP	NM_031433.4	c.*1540T>C		3_prime_UTR_variant	Exon 15 of 15	ENST00000619721.6	NP_113621.1
C1QTNF5	NM_015645.5	c.644T>C	p.Ile215Thr	missense_variant	Exon 15 of 15		NP_056460.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
C1QTNF5	ENST00000528368.3	c.644T>C	p.Ile215Thr	missense_variant	Exon 3 of 3	1	NM_001278431.2	ENSP00000431140.1
C1QTNF5	ENST00000530681.2	c.644T>C	p.Ile215Thr	missense_variant	Exon 2 of 2	1		ENSP00000456533.2
MFRP	ENST00000619721.6	c.*1540T>C		3_prime_UTR_variant	Exon 15 of 15	1	NM_031433.4	ENSP00000481824.1
C1QTNF5	ENST00000525657.2	n.534T>C		non_coding_transcript_exon_variant	Exon 2 of 2	2

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 151992 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000161 AC: 4 AN: 248282 AF XY: 0.0000223

Gnomad AFR exome AF: 0.0000616

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000109

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461450 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 726984

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26108

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.0000696 AC: 6 AN: 86232

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53370

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

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111718

Other (OTH) AF: 0.0000166 AC: 1 AN: 60368

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 151992 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74244

African (AFR) AF: 0.0000483 AC: 2 AN: 41398

American (AMR) AF: 0.00 AC: 0 AN: 15278

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 5156

South Asian (SAS) AF: 0.00 AC: 0 AN: 4808

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10592

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 67978

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000264

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Retinal degeneration Uncertain:1

Jun 14, 2016

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Isolated microphthalmia 5 Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not provided Uncertain:1

Feb 18, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 302924). This variant has not been reported in the literature in individuals affected with C1QTNF5-related conditions. This variant is present in population databases (rs779732274, gnomAD 0.01%). This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 215 of the C1QTNF5 protein (p.Ile215Thr). -

Late-onset retinal degeneration Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.094
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.37
CADD	Benign	18
DANN	Benign	0.83
DEOGEN2	Benign	0.16	T;T
Eigen	Benign	-0.20
Eigen_PC	Benign	-0.13
FATHMM_MKL	Benign	0.31	N
LIST_S2	Benign	0.73	.;T
M_CAP	Benign	0.037	D
MetaRNN	Benign	0.18	T;T
MetaSVM	Benign	-0.85	T
MutationAssessor	Benign	-0.39	N;N
PhyloP100		0.50
PrimateAI	Benign	0.46	T
PROVEAN	Benign	2.1	N;.
REVEL	Benign	0.14
Sift	Benign	0.43	T;.
Sift4G	Benign	0.98	T;T
Vest4		0.20
MutPred		0.56		Gain of relative solvent accessibility (P = 0.0249);Gain of relative solvent accessibility (P = 0.0249);
MVP		0.38
ClinPred		0.063	T
GERP RS		4.4
Varity_R		0.26
gMVP		0.23
Mutation Taster		=80/20	polymorphism

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: rs779732274; hg19: chr11-119210129;