4-1801928-A-G

Position:

• chr4-1801928-A-G

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_000142.5(FGFR3):​c.833A>G​(p.Tyr278Cys) 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 Pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: FGFR3 NM_000142.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3 O:1
• Conservation: PhyloP100: 6.96

Genes affected

FGFR3 (HGNC:3690): (fibroblast growth factor receptor 3) This gene encodes a member of the fibroblast growth factor receptor (FGFR) family, with its amino acid sequence being highly conserved between members and among divergent species. FGFR family members differ from one another in their ligand affinities and tissue distribution. A full-length representative protein would consist of an extracellular region, composed of three immunoglobulin-like domains, a single hydrophobic membrane-spanning segment and a cytoplasmic tyrosine kinase domain. The extracellular portion of the protein interacts with fibroblast growth factors, setting in motion a cascade of downstream signals, ultimately influencing mitogenesis and differentiation. This particular family member binds acidic and basic fibroblast growth hormone and plays a role in bone development and maintenance. Mutations in this gene lead to craniosynostosis and multiple types of skeletal dysplasia. [provided by RefSeq, Aug 2017]

FGFR3 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.945
• PP5: Variant 4-1801928-A-G is Pathogenic according to our data. Variant chr4-1801928-A-G is described in ClinVar as [Pathogenic]. Clinvar id is 16357.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FGFR3	NM_000142.5	c.833A>G	p.Tyr278Cys	missense_variant	7/18	ENST00000440486.8	NP_000133.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FGFR3	ENST00000440486.8	c.833A>G	p.Tyr278Cys	missense_variant	7/18	5	NM_000142.5	ENSP00000414914.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 38

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypochondroplasia Pathogenic:1 Other:1

Pathogenic, no assertion criteria provided	literature only	OMIM	Dec 01, 2006	- -
not provided, no classification provided	literature only	GeneReviews	-	Phenotype resembles achondroplasia in newborns [Heuertz et al 2006, Song et al 2012]. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 01, 2023

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 278 of the FGFR3 protein (p.Tyr278Cys). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with hypochondroplasia (PMID: 16912704, 24411048, 29595812). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 16357). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (Invitae) indicates that this missense variant is expected to disrupt FGFR3 function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Short stature Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Jun 23, 2015

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.59	D;T;.;.;T;.
Eigen	Uncertain	0.39
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;.
M_CAP	Pathogenic	0.51	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D;D
MetaSVM	Uncertain	0.094	D
MutationAssessor	Benign	0.72	N;.;N;N;.;N
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-6.9	D;D;D;D;.;D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.0020	D;D;D;D;.;D
Sift4G	Uncertain	0.014	D;D;D;D;D;D
Polyphen		1.0	D;D;D;D;.;D
Vest4		0.94
MutPred		0.70		Loss of catalytic residue at Y278 (P = 0.0407);Loss of catalytic residue at Y278 (P = 0.0407);Loss of catalytic residue at Y278 (P = 0.0407);Loss of catalytic residue at Y278 (P = 0.0407);Loss of catalytic residue at Y278 (P = 0.0407);Loss of catalytic residue at Y278 (P = 0.0407);
MVP		0.92
MPC		1.1
ClinPred		1.0	D
GERP RS		3.9
Varity_R		0.90
gMVP		0.90

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		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: rs121913115; hg19: chr4-1803655;