17-81528586-G-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_012418.4(FSCN2):c.55G>A(p.Asp19Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000106 in 1,608,892 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D19V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 34)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: FSCN2 NM_012418.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.96

Genes affected

FSCN2 (HGNC:3960): (fascin actin-bundling protein 2, retinal) This gene encodes a member of the fascin protein family. Fascins crosslink actin into filamentous bundles within dynamic cell extensions. This family member is proposed to play a role in photoreceptor disk morphogenesis. A mutation in this gene results in one form of autosomal dominant retinitis pigmentosa and macular degeneration. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.08161983).
• BS2: High AC in GnomAdExome at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FSCN2	NM_012418.4	c.55G>A	p.Asp19Asn	missense_variant	1/5	ENST00000417245.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FSCN2	ENST00000417245.7	c.55G>A	p.Asp19Asn	missense_variant	1/5	1	NM_012418.4	P1
FSCN2	ENST00000334850.7	c.55G>A	p.Asp19Asn	missense_variant	1/5	5

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152244 Hom.: 0 Cov.: 34

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000209 AC: 5 AN: 238708 Hom.: 0 AF XY: 0.0000230 AC XY: 3 AN XY: 130316

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: 0.000169

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000103 AC: 15 AN: 1456648 Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8 AN XY: 724196

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000117

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.0000332

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152244 Hom.: 0 Cov.: 34 AF XY: 0.0000134 AC XY: 1 AN XY: 74380

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.0000166 AC: 2

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 27, 2023

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 19 of the FSCN2 protein (p.Asp19Asn). This variant is present in population databases (rs781918011, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with FSCN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 971078). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.091
BayesDel_addAF	Benign	-0.48	T
BayesDel_noAF	Benign	-0.67
Cadd	Benign	21
Dann	Benign	0.92
DEOGEN2	Benign	0.065	T;.
Eigen	Benign	-0.65
Eigen_PC	Benign	-0.59
FATHMM_MKL	Benign	0.52	D
LIST_S2	Uncertain	0.91	D;D
M_CAP	Benign	0.016	T
MetaRNN	Benign	0.082	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.55	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Uncertain	0.53	T
PROVEAN	Benign	0.23	N;N
REVEL	Benign	0.030
Sift	Benign	1.0	T;T
Sift4G	Benign	1.0	T;T
Polyphen		0.071	B;.
Vest4		0.28
MutPred		0.32		Loss of catalytic residue at D19 (P = 0.097);Loss of catalytic residue at D19 (P = 0.097);
MVP		0.37
MPC		0.12
ClinPred		0.043	T
GERP RS		4.2
Varity_R		0.060
gMVP		0.39

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: rs781918011; hg19: chr17-79495612; COSMIC: COSV58368425; COSMIC: COSV58368425;