20-17494136-C-T

Position:

chr20-17494136-C-T

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2BP4_ModerateBS1_Supporting

The NM_001195.5(BFSP1):c.1936G>A(p.Val646Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000558 in 1,614,152 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

BFSP1
NM_001195.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 5.55

Variant links:

Genes affected

BFSP1 (HGNC:1040): (beaded filament structural protein 1) This gene encodes a lens-specific intermediate filament-like protein named filensin. The encoded protein is expressed in lens fiber cells after differentiation has begun. This protein functions as a component of the beaded filament which is a cytoskeletal structure found in lens fiber cells. Mutations in this gene are the cause of autosomal recessive cortical juvenile-onset cataract. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

BFSP1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.082327455).

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000256 (39/152336) while in subpopulation AFR AF= 0.000866 (36/41566). AF 95% confidence interval is 0.000643. There are 0 homozygotes in gnomad4. There are 18 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BFSP1	NM_001195.5 linkuse as main transcript	c.1936G>A	p.Val646Met	missense_variant	8/8	ENST00000377873.8	NP_001186.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BFSP1	ENST00000377873.8 linkuse as main transcript	c.1936G>A	p.Val646Met	missense_variant	8/8	1	NM_001195.5	ENSP00000367104	P1	Q12934-1
BFSP1	ENST00000377868.6 linkuse as main transcript	c.1561G>A	p.Val521Met	missense_variant	8/8	1		ENSP00000367099		Q12934-2
BFSP1	ENST00000536626.7 linkuse as main transcript	c.1519G>A	p.Val507Met	missense_variant	9/9	2		ENSP00000442522		Q12934-3

Frequencies

GnomAD3 genomes

AF:

0.000256

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000869

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000875

AC:

AN:

251350

Hom.:

AF XY:

0.0000589

AC XY:

AN XY:

135866

show subpopulations

Gnomad AFR exome

AF:

0.000923

Gnomad AMR exome

AF:

0.000174

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000349

AC:

AN:

1461816

Hom.:

Cov.:

AF XY:

0.0000261

AC XY:

AN XY:

727212

show subpopulations

Gnomad4 AFR exome

AF:

0.000986

Gnomad4 AMR exome

AF:

0.000157

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000899

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.000256

AC:

AN:

152336

Hom.:

Cov.:

AF XY:

0.000242

AC XY:

AN XY:

74504

show subpopulations

Gnomad4 AFR

AF:

0.000866

Gnomad4 AMR

AF:

0.0000653

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000191

Hom.:

Bravo

AF:

0.000302

ESP6500AA

AF:

0.000681

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000741

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 16, 2020

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Cataract 33

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 01, 2018

This sequence change replaces valine with methionine at codon 646 of the BFSP1 protein (p.Val646Met). The valine residue is highly conserved and there is a small physicochemical difference between valine and methionine. This variant is present in population databases (rs145017887, ExAC 0.08%). This variant has not been reported in the literature in individuals with BFSP1-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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

0.20

BayesDel_addAF

Benign

-0.25

BayesDel_noAF

Benign

-0.20

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.22

T;.;.

Eigen

Uncertain

0.59

Eigen_PC

Uncertain

0.52

FATHMM_MKL

Uncertain

0.95

LIST_S2

Benign

0.83

T;T;T

M_CAP

Uncertain

0.12

MetaRNN

Benign

0.082

T;T;T

MetaSVM

Uncertain

-0.19

MutationAssessor

Uncertain

2.5

M;.;.

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Uncertain

0.52

PROVEAN

Benign

-1.6

N;D;D

REVEL

Benign

0.26

Sift

Pathogenic

0.0

D;D;D

Sift4G

Pathogenic

0.0

D;.;D

Polyphen

1.0

D;D;.

Vest4

0.37

MVP

0.67

MPC

0.43

ClinPred

0.15

GERP RS

4.1

Varity_R

0.30

gMVP

0.43

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over