4-1806668-A-C

Position:

• chr4-1806668-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_000142.5(FGFR3):​c.2153A>C​(p.Asn718Thr) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N718S) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: FGFR3 NM_000142.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.98

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a domain Protein kinase (size 289) in uniprot entity FGFR3_HUMAN there are 14 pathogenic changes around while only 5 benign (74%) in NM_000142.5
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FGFR3	NM_000142.5	c.2153A>C	p.Asn718Thr	missense_variant	16/18	ENST00000440486.8	NP_000133.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FGFR3	ENST00000440486.8	c.2153A>C	p.Asn718Thr	missense_variant	16/18	5	NM_000142.5	ENSP00000414914	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000400 AC: 1 AN: 249702 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135576

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000888

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 39

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Uncertain	0.066	T
BayesDel_noAF	Benign	-0.14
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.82	D;.;.;.
Eigen	Uncertain	0.19
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.90	D;D;D;.
M_CAP	Uncertain	0.25	D
MetaRNN	Uncertain	0.52	D;D;D;D
MetaSVM	Benign	-0.54	T
MutationAssessor	Benign	1.2	L;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;N
PrimateAI	Uncertain	0.73	T
PROVEAN	Uncertain	-3.4	D;D;D;D
REVEL	Uncertain	0.41
Sift	Benign	0.17	T;T;T;T
Sift4G	Benign	0.32	T;T;T;T
Polyphen		0.0090	B;P;B;B
Vest4		0.57
MutPred		0.56		Gain of phosphorylation at N718 (P = 0.015);.;.;.;
MVP		0.91
MPC		0.055
ClinPred		0.51	D
GERP RS		3.2
Varity_R		0.22
gMVP		0.68

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: rs139773438; hg19: chr4-1808395;