5-171456678-G-A

Position:

• chr5-171456678-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_003862.3(FGF18):​c.497G>A​(p.Arg166Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: FGF18 NM_003862.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.24

Genes affected

FGF18 (HGNC:3674): (fibroblast growth factor 18) The protein encoded by this gene is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth, and invasion. It has been shown in vitro that this protein is able to induce neurite outgrowth in PC12 cells. Studies of the similar proteins in mouse and chick suggested that this protein is a pleiotropic growth factor that stimulates proliferation in a number of tissues, most notably the liver and small intestine. Knockout studies of the similar gene in mice implied the role of this protein in regulating proliferation and differentiation of midline cerebellar structures. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.4198168).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FGF18	NM_003862.3	c.497G>A	p.Arg166Gln	missense_variant	5/5	ENST00000274625.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FGF18	ENST00000274625.6	c.497G>A	p.Arg166Gln	missense_variant	5/5	1	NM_003862.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 08, 2023

The c.497G>A (p.R166Q) alteration is located in exon 5 (coding exon 5) of the FGF18 gene. This alteration results from a G to A substitution at nucleotide position 497, causing the arginine (R) at amino acid position 166 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.095
BayesDel_addAF	Benign	-0.069	T
BayesDel_noAF	Benign	-0.34
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.85	D
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Uncertain	0.78	D
LIST_S2	Uncertain	0.94	D
M_CAP	Benign	0.038	D
MetaRNN	Benign	0.42	T
MetaSVM	Pathogenic	0.87	D
MutationAssessor	Benign	1.5	L
MutationTaster	Benign	0.81	D
PrimateAI	Uncertain	0.59	T
PROVEAN	Uncertain	-2.7	D
REVEL	Uncertain	0.37
Sift	Uncertain	0.020	D
Sift4G	Uncertain	0.029	D
Polyphen		1.0	D
Vest4		0.065
MutPred		0.43		Loss of MoRF binding (P = 0.038);
MVP		0.87
MPC		1.2
ClinPred		0.96	D
GERP RS		5.3
Varity_R		0.56
gMVP		0.59

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: rs1772586453; hg19: chr5-170883682;