6-31946457-G-A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Strong

The NM_001710.6(CFB):​c.149G>A​(p.Arg50Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,612,924 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

CFB
NM_001710.6 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.798
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.043850064).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CFBNM_001710.6 linkc.149G>A p.Arg50Gln missense_variant Exon 2 of 18 ENST00000425368.7 NP_001701.2 P00751-1A0A1U9X7H8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CFBENST00000425368.7 linkc.149G>A p.Arg50Gln missense_variant Exon 2 of 18 1 NM_001710.6 ENSP00000416561.2 P00751-1
ENSG00000244255ENST00000456570.5 linkc.1655G>A p.Arg552Gln missense_variant Exon 14 of 30 2 ENSP00000410815.1 B4E1Z4

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152150
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000458
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000649
AC:
16
AN:
246616
Hom.:
0
AF XY:
0.0000372
AC XY:
5
AN XY:
134426
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000406
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:
0.0000181
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1460774
Hom.:
0
Cov.:
33
AF XY:
0.00000826
AC XY:
6
AN XY:
726704
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000291
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:
0.00000540
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152150
Hom.:
0
Cov.:
31
AF XY:
0.0000673
AC XY:
5
AN XY:
74324
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.000458
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.000117
ExAC
AF:
0.0000593
AC:
7

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Uncertain:1
Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 50 of the CFB protein (p.Arg50Gln). This variant is present in population databases (rs769314843, gnomAD 0.04%), and has an allele count higher than expected for a pathogenic variant. This variant has not been reported in the literature in individuals affected with CFB-related conditions. ClinVar contains an entry for this variant (Variation ID: 1422280). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt CFB protein function with a negative predictive value of 80%. 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
0.063
BayesDel_addAF
Benign
-0.40
T
BayesDel_noAF
Benign
-0.49
CADD
Benign
7.5
DANN
Uncertain
0.99
DEOGEN2
Benign
0.091
.;.;T
Eigen
Benign
-1.1
Eigen_PC
Benign
-0.97
FATHMM_MKL
Benign
0.060
N
LIST_S2
Benign
0.69
T;T;T
M_CAP
Benign
0.014
T
MetaRNN
Benign
0.044
T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-0.59
.;.;N
PrimateAI
Benign
0.20
T
PROVEAN
Benign
-0.24
N;N;N
REVEL
Benign
0.15
Sift
Benign
0.28
T;T;T
Sift4G
Benign
0.35
T;T;T
Polyphen
0.031
.;.;B
Vest4
0.050
MutPred
0.62
Gain of ubiquitination at K547 (P = 0.0527);.;.;
MVP
0.26
MPC
0.54
ClinPred
0.081
T
GERP RS
-3.0
Varity_R
0.18
gMVP
0.31

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.

Other links and lift over

dbSNP: rs769314843; hg19: chr6-31914234; API