4-1805643-A-C

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000142.5(FGFR3):​c.1619A>C​(p.Asn540Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,880 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N540D) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 34)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

FGFR3
NM_000142.5 missense

Scores

9
8
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 8.73

Publications

38 publications found
Variant links:
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)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000142.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr4-1805642-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 374828.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.993
PP5
Variant 4-1805643-A-C is Pathogenic according to our data. Variant chr4-1805643-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 16344.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
FGFR3NM_000142.5 linkc.1619A>C p.Asn540Thr missense_variant Exon 12 of 18 ENST00000440486.8 NP_000133.1 P22607-1Q0IJ44

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FGFR3ENST00000440486.8 linkc.1619A>C p.Asn540Thr missense_variant Exon 12 of 18 5 NM_000142.5 ENSP00000414914.2 P22607-1

Frequencies

GnomAD3 genomes
Cov.:
34
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460880
Hom.:
0
Cov.:
34
AF XY:
0.00000138
AC XY:
1
AN XY:
726800
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33462
American (AMR)
AF:
0.00
AC:
0
AN:
44698
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39688
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52818
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111724
Other (OTH)
AF:
0.00
AC:
0
AN:
60358
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
34
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:4
Jun 03, 2020
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant has been observed in individual(s) with clinical features of autosomal dominant hypochondroplasia (PMID: 9452043, Invitae). It has also been observed to segregate with disease in related individuals. This variant is also known as c.1658A>C in the literature. ClinVar contains an entry for this variant (Variation ID: 16344). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant disrupts the p.Asn540 amino acid residue in FGFR3. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 7670477, 8589686, 9452043, 25614871). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency). This sequence change replaces asparagine with threonine at codon 540 of the FGFR3 protein (p.Asn540Thr). The asparagine residue is highly conserved and there is a small physicochemical difference between asparagine and threonine. -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Dec 11, 2023
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25728633, 9452043, 30048571, 30681580, 35438268) -

Hypochondroplasia Pathogenic:2
Jan 01, 1998
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

-
Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.75
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Uncertain
0.060
CADD
Pathogenic
26
DANN
Uncertain
0.98
DEOGEN2
Pathogenic
0.90
D;D;.;.;.
Eigen
Uncertain
0.50
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.94
D;D;D;D;.
M_CAP
Pathogenic
0.79
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D
MetaSVM
Uncertain
0.60
D
MutationAssessor
Benign
0.90
L;.;.;.;.
PhyloP100
8.7
PrimateAI
Uncertain
0.79
T
PROVEAN
Pathogenic
-5.3
D;D;D;D;D
REVEL
Pathogenic
0.80
Sift
Pathogenic
0.0
D;D;D;D;D
Sift4G
Uncertain
0.0020
D;D;D;D;D
Polyphen
1.0
D;D;D;D;D
Vest4
0.97
MutPred
0.97
Loss of stability (P = 0.0691);.;.;.;.;
MVP
0.96
MPC
0.98
ClinPred
1.0
D
GERP RS
4.9
Varity_R
0.93
gMVP
0.73
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

Publications

Other links and lift over

dbSNP: rs77722678; hg19: chr4-1807370; API