6-31946285-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001710.6(CFB):c.64G>A(p.Gly22Ser) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.00000186 in 1,612,982 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 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

CFB
NM_001710.6 missense, splice_region

Scores

Splicing: ADA: 0.8081

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.41

Variant links:

Genes affected

CFB (HGNC:1037): (complement factor B) This gene encodes complement factor B, a component of the alternative pathway of complement activation. Factor B circulates in the blood as a single chain polypeptide. Upon activation of the alternative pathway, it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. The active subunit Bb is a serine protease which associates with C3b to form the alternative pathway C3 convertase. Bb is involved in the proliferation of preactivated B lymphocytes, while Ba inhibits their proliferation. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. This cluster includes several genes involved in regulation of the immune reaction. Polymorphisms in this gene are associated with a reduced risk of age-related macular degeneration. The polyadenylation site of this gene is 421 bp from the 5' end of the gene for complement component 2. [provided by RefSeq, Jul 2008]

CFB links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CFB	NM_001710.6 linkuse as main transcript	c.64G>A	p.Gly22Ser	missense_variant, splice_region_variant	1/18	ENST00000425368.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CFB	ENST00000425368.7 linkuse as main transcript	c.64G>A	p.Gly22Ser	missense_variant, splice_region_variant	1/18	1	NM_001710.6	P1	P00751-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152200

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.85e-7

AC:

AN:

1460782

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726706

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000191

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152200

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74348

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 26, 2021

This variant is not present in population databases (ExAC no frequency). 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with CFB-related conditions. This sequence change replaces glycine with serine at codon 22 of the CFB protein (p.Gly22Ser). The glycine residue is weakly conserved and there is a small physicochemical difference between glycine and serine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.093

BayesDel_addAF

Benign

-0.056

BayesDel_noAF

Benign

-0.32

Cadd

Pathogenic

Dann

Benign

0.90

Eigen

Benign

0.073

Eigen_PC

Benign

0.11

FATHMM_MKL

Uncertain

0.92

LIST_S2

Benign

0.82

T;T

M_CAP

Benign

0.077

MetaRNN

Benign

0.32

T;T

MetaSVM

Benign

-0.62

MutationTaster

Benign

0.96

D;D

PROVEAN

Benign

-1.2

N;N

REVEL

Benign

0.15

Sift

Benign

0.48

T;T

Sift4G

Uncertain

0.036

D;D

Polyphen

0.97

.;D

Vest4

0.21

MutPred

0.47

Gain of glycosylation at G22 (P = 0.0512);Gain of glycosylation at G22 (P = 0.0512);

MVP

0.84

MPC

0.48

ClinPred

0.60

GERP RS

4.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.8

Varity_R

0.080

gMVP

0.67

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.81

dbscSNV1_RF

Pathogenic

0.74

SpliceAI score (max)

0.38

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.38

Position offset: 0

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