rs1554100945

Positions:

• chr6-1610680-C-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_001453.3(FOXC1):​c.235C>T​(p.Pro79Ser) variant causes a missense change. 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P79Q) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: FOXC1 NM_001453.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.03

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_001453.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr6-1610681-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 2571241.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.987

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FOXC1	NM_001453.3	c.235C>T	p.Pro79Ser	missense_variant	1/1	ENST00000645831.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FOXC1	ENST00000645831.2	c.235C>T	p.Pro79Ser	missense_variant	1/1		NM_001453.3	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Axenfeld-Rieger syndrome type 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 23, 2017

This sequence change replaces proline with serine at codon 79 of the FOXC1 protein (p.Pro79Ser). The proline residue is highly conserved and there is a moderate physicochemical difference between proline and serine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with FOXC1-related disease. 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 disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. Different missense substitutions at this codon (p.Pro79Leu, p.Pro79Thr, and p.Pro79Arg) have been reported in individuals affected with anterior segment dysgenesis and Axenfeld-Rieger syndrome (PMID: 11170889, 16936096), and at least one (p.Pro79Thr) has been determined to be pathogenic (PMID: 14506133, 27124303, 11589884). This suggests that the proline residue is critical for FOXC1 protein function and that other missense substitutions at this position may also be pathogenic. 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	1.0
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D;D
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.71
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Pathogenic	1.0	.;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Pathogenic	3.6	H;H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-7.4	D;.
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0	D;.
Polyphen		1.0	D;D
Vest4		0.77
MutPred		0.88		Loss of catalytic residue at P79 (P = 0.0029);Loss of catalytic residue at P79 (P = 0.0029);
MVP		0.99
ClinPred		1.0	D
GERP RS		3.9
Varity_R		0.96
gMVP		0.94

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: rs1554100945; hg19: chr6-1610915;