6-1610850-C-A

Variant names:

• chr6-1610850-C-A
• rs2230096
• NM_001453.3:c.405C>A

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001453.3(FOXC1):​c.405C>A​(p.Cys135*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. C135C) has been classified as Benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: FOXC1 NM_001453.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.75
• Publications: 3 publications found

Genes affected

FOXC1 (HGNC:3800): (forkhead box C1) This gene belongs to the forkhead family of transcription factors which is characterized by a distinct DNA-binding forkhead domain. The specific function of this gene has not yet been determined; however, it has been shown to play a role in the regulation of embryonic and ocular development. Mutations in this gene cause various glaucoma phenotypes including primary congenital glaucoma, autosomal dominant iridogoniodysgenesis anomaly, and Axenfeld-Rieger anomaly. [provided by RefSeq, Jul 2008]

FOXC1 Gene-Disease associations (from GenCC):

• anterior segment dysgenesis 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae)
• Axenfeld-Rieger syndrome type 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• aniridia

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• Axenfeld anomaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Axenfeld-Rieger syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• isolated aniridia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Peters anomaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Rieger anomaly

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 74 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 6-1610850-C-A is Pathogenic according to our data. Variant chr6-1610850-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 857470.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FOXC1	NM_001453.3	c.405C>A	p.Cys135*	stop_gained	Exon 1 of 1	ENST00000645831.2	NP_001444.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FOXC1	ENST00000645831.2	c.405C>A	p.Cys135*	stop_gained	Exon 1 of 1		NM_001453.3	ENSP00000493906.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Axenfeld-Rieger syndrome type 3 Pathogenic:1

Feb 14, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals with FOXC1-related conditions. This sequence change results in a premature translational stop signal in the FOXC1 gene (p.Cys135*). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 419 amino acids of the FOXC1 protein. This variant is not present in population databases (ExAC no frequency). This variant disrupts the C-terminus of the FOXC1 protein. Other variant(s) that disrupt this region (p.Ser320Argfs*81) have been determined to be pathogenic (Invitae). This suggests that variants that disrupt this region of the protein are likely to be causative of disease. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	39
DANN	Uncertain	0.99
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Uncertain	0.95	D
PhyloP100		2.8
Vest4		0.89
GERP RS		3.7
Mutation Taster		=1/199	disease causing (ClinVar)

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: rs2230096; hg19: chr6-1611085;