4-1801841-CC-GT

Variant names:

• chr4-1801841-CC-GT
• NM_000142.5:c.746_747delCCinsGT
• FGFR3 p.Ser249Cys

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PS1_Very_Strong PM1 PM5

The NM_000142.5(FGFR3):​c.746_747delCCinsGT​(p.Ser249Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S249Y) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: FGFR3 NM_000142.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.48
• Publications: 0 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: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp, G2P, Ambry Genetics, ClinGen
• Crouzon syndrome-acanthosis nigricans syndrome

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

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

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

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

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• thanatophoric dysplasia type 1

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

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

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

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, 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 12 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, 8 uncertain in NM_000142.5
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr4-1801841-C-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 4056874.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000142.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FGFR3	NM_000142.5	MANE Select	c.746_747delCCinsGT	p.Ser249Cys	missense	N/A	NP_000133.1	P22607-1
	FGFR3	NM_001163213.2		c.746_747delCCinsGT	p.Ser249Cys	missense	N/A	NP_001156685.1	P22607-2
	FGFR3	NM_001354809.2		c.746_747delCCinsGT	p.Ser249Cys	missense	N/A	NP_001341738.1	X5D2G8

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FGFR3	ENST00000440486.8	TSL:5 MANE Select	c.746_747delCCinsGT	p.Ser249Cys	missense	N/A	ENSP00000414914.2	P22607-1
	FGFR3	ENST00000481110.7	TSL:1	c.746_747delCCinsGT	p.Ser249Cys	missense	N/A	ENSP00000420533.2	F8W9L4
	FGFR3	ENST00000352904.6	TSL:1	c.746_747delCCinsGT	p.Ser249Cys	missense	N/A	ENSP00000231803.1	P22607-3

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.5

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr4-1803568;