NM_000142.5:c.1138G>C

Variant names:

• chr4-1804392-G-C
• rs28931614
• NM_000142.5:c.1138G>C

Variant summary

Our verdict is Pathogenic. The variant received 24 ACMG points: 24P and 0B. PS1_Very_Strong PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_000142.5(FGFR3):​c.1138G>C​(p.Gly380Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,460,854 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: FGFR3 NM_000142.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:12 O:1
• Conservation: PhyloP100: 4.38
• Publications: 460 publications found

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 Gene-Disease associations (from GenCC):

• achondroplasia

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, ClinGen, Genomics England PanelApp, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Crouzon syndrome-acanthosis nigricans syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia, ClinGen
• hypochondroplasia

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, G2P, ClinGen, Labcorp Genetics (formerly Invitae), Orphanet
• lacrimoauriculodentodigital syndrome 2

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• Muenke syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, ClinGen, G2P
• thanatophoric dysplasia type 1

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Genomics England PanelApp, Orphanet, ClinGen
• thanatophoric dysplasia type 2

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
• camptodactyly-tall stature-scoliosis-hearing loss syndrome

  Inheritance: AR, AD, SD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, G2P, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
• severe achondroplasia-developmental delay-acanthosis nigricans syndrome

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
• isolated brachycephaly

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• LADD syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• LADD syndrome 1

  Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 24 ACMG points.

• PS1: Transcript NM_000142.5 (FGFR3) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 14 uncertain in NM_000142.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984
• PP5: Variant 4-1804392-G-C is Pathogenic according to our data. Variant chr4-1804392-G-C is described in ClinVar as Pathogenic. ClinVar VariationId is 16328.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FGFR3	NM_000142.5	c.1138G>C	p.Gly380Arg	missense_variant	Exon 9 of 18	ENST00000440486.8	NP_000133.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FGFR3	ENST00000440486.8	c.1138G>C	p.Gly380Arg	missense_variant	Exon 9 of 18	5	NM_000142.5	ENSP00000414914.2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460854 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 726746

African (AFR) AF: 0.00 AC: 0 AN: 33468

American (AMR) AF: 0.00 AC: 0 AN: 44688

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26110

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86202

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52864

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111700

Other (OTH) AF: 0.00 AC: 0 AN: 60366

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:12 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:5

Jan 27, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 380 of the FGFR3 protein (p.Gly380Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with achondroplasia (PMID: 8723101, 21739570, 22045636, 22339077, 25614871, 25691418). ClinVar contains an entry for this variant (Variation ID: 16328). Invitae Evidence Modeling incorporating data from in vitro experimental studies (internal data) 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.

Feb 21, 2017

Eurofins Ntd Llc (ga)

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Apr 02, 2021

Revvity Omics, Revvity

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Mar 17, 2025

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

More than 99% of cases of achondroplasia are caused by this variant and another point mutation (c.1138 G>A) resulting in arginine-for-glycine substitutions in amino acid 380 of the gene (PMID: 22045636, 7913883); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 33370388, 31566912, 33368972, 28679403, 8078586, 8723101, 33511985, 25614871, 17683901, 25691418, 9857065, 23056398, 19088846, 28230213, 29593476, 21739570, 22339077, 22325359, 28181399, 30160829, 30138938, 34672771, 36352425, 36923788, 38702915, 29542187, 22045636, 7913883)

Apr 28, 2021

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The FGFR3 c.1138G>C; p.Gly380Arg variant (rs28931614) is a common pathogenic variant observed in individuals affected with achondroplasia (Rousseau 1994, Xue 2014). This variant is absent from general population databases (Exome Variant Server, Genome Aggregation Database), indicating it is not a common polymorphism. Functional characterization of the variant protein suggests it causes ligand-independent phosphorylation of ERK and reduced proliferation of chondrocytes (Krejci 2008). A mouse model expressing the p.Gly380Arg variant recapitulates skeletal alterations observed in human achondroplasia patients (Lee 2017). Additionally, another variant at this codon causing the same amino substitution (c.1138G>A; p.Gly380Arg) is commonly reported in individuals with achondroplasia and is considered pathogenic (Rousseau 1994, Xue 2014). Based on available information, the c.1138G>C; p.Gly380Arg variant is considered to be pathogenic. References: Krejci P et al. Analysis of STAT1 activation by six FGFR3 mutants associated with skeletal dysplasia undermines dominant role of STAT1 in FGFR3 signaling in cartilage. PLoS One. 2008;3(12):e3961.. PMID: 19088846. Lee YC et al. Knock-in human FGFR3 achondroplasia mutation as a mouse model for human skeletal dysplasia. Sci Rep. 2017 Feb 23;7:43220. PMID: 28230213. Rousseau F et al. Mutations in the gene encoding fibroblast growth factor receptor-3 in achondroplasia. Nature. 1994 Sep 15;371(6494):252-4. PMID: 8078586. Xue Y et al. FGFR3 mutation frequency in 324 cases from the International Skeletal Dysplasia Registry. Mol Genet Genomic Med. 2014 Nov;2(6):497-503. PMID: 25614871.

Achondroplasia Pathogenic:4

Sep 15, 1994

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Neuberg Centre For Genomic Medicine, NCGM

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Sep 01, 2022

3billion

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant is not observed in the gnomAD v2.1.1 dataset. Missense changes are a common disease-causing mechanism. In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.71; 3Cnet: 0.92). Same nucleotide change resulting in same amino acid change has been previously reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000016328). The variant has been observed in multiple (>3) similarly affected unrelated individuals (PMID: 25614871). A different missense change at the same codon (p.Gly380Lys) has been reported to be associated with FGFR3-related disorder (PMID: 17256796). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline.

May 06, 2021

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0103 - Gain of function is a known mechanism of disease in this gene and are associated with skeletal dysplasias (MIM#146000, #100800, #187600, #187601; PMID: 17320202). Loss of function and dominant negative mechanisms have been proposed to cause autosomal recessive and dominant CATSHL syndrome, respectively (MIM#610474; PMID: 17033969, 24864036). (I) 0108 - This gene is associated with both recessive and dominant disease. Although predominantly associated with dominant disease, at least one family has been described with autosomal recessive CATSHL syndrome (PMID: 24864036). (I) 0115 - Variants in this gene are known to have variable expressivity. Variants typically associated with achondroplasia have also been reported in individuals with hypochondroplasia (PMID: 25614871). (I) 0200 - Variant is predicted to result in a missense amino acid change from glycine to arginine. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0600 - Variant is located in the annotated transmembrane domain (UniProt). (I) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. The variants c.1138G>A and c.1138G>C, both resulting in the missense change p.(Gly380Arg), are commonly reported pathogenic and account for approximately 90% of achondroplasia cases with variants in this gene (ClinVar, PMID: 25614871). (SP) 1204 - This variant has been shown to be de novo in the proband (parental status not tested but assumed). (SP) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign

Hypochondroplasia Pathogenic:1 Other:1

May 28, 2019

Mendelics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Common pathogenic variant in achondroplasia

Achondroplasia;C0005684:Malignant tumor of urinary bladder;C0334082:Epidermal nevus;C0346629:Colorectal cancer;C0410529:Hypochondroplasia;C1300257:Thanatophoric dysplasia, type 2;C1336708:Germ cell tumor of testis;C1864436:Muenke syndrome;C1864852:Camptodactyly-tall stature-scoliosis-hearing loss syndrome;C1868678:Thanatophoric dysplasia type 1;C2674173:Severe achondroplasia-developmental delay-acanthosis nigricans syndrome;C2677099:Crouzon syndrome-acanthosis nigricans syndrome;C4048328:Cervical cancer;C5774323:LADD syndrome 1 Pathogenic:1

Juno Genomics, Hangzhou Juno Genomics, Inc

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Absent from controls (or at extremely low frequency if recessive) in Genome Aggregation Database, Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium.;The prevalence of the variant in affected individuals is significantly increased compared to the prevalence in controls.;Well-established in vitro or in vivo functional studies supportive of a damaging effect on the gene or gene product.;Same amino acid change as a previously established pathogenic variant regardless of nucleotide change.;Patient's phenotype or family history is highly specific for a disease with a single genetic etiology.

FGFR3-related disorder Pathogenic:1

Aug 23, 2024

PreventionGenetics, part of Exact Sciences

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The FGFR3 c.1138G>C variant is predicted to result in the amino acid substitution p.Gly380Arg. The p.Gly380Arg variant has been well documented to be causative for autosomal dominant achondroplasia (see examples: Shiang et al. 1994. PubMed ID: 7913883; Bellus et al. 1995. PubMed ID: 7847369). This variant has not been reported in gnomAD, indicating this variant is rare. This variant is interpreted as pathogenic.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.21
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.69	D;T;.
Eigen	Uncertain	0.33
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D;D;D
M_CAP	Pathogenic	0.43	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Uncertain	0.38	D
MutationAssessor	Benign	1.5	L;.;.
PhyloP100		4.4
PrimateAI	Uncertain	0.55	T
PROVEAN	Benign	-1.1	N;N;N
REVEL	Pathogenic	0.71
Sift	Uncertain	0.016	D;T;D
Sift4G	Benign	0.14	T;T;T
Vest4		0.86
ClinPred		0.89	D
GERP RS		3.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.71
gMVP		0.82
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs28931614; hg19: chr4-1806119; COSMIC: COSV99602429; COSMIC: COSV99602429;