chr1-22659553-G-A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3

The NM_001378156.1(C1QB):​c.91G>A​(p.Gly31Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000335 in 1,613,994 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

C1QB
NM_001378156.1 missense

Scores

3
5
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.69

Publications

1 publications found
Variant links:
Genes affected
C1QB (HGNC:1242): (complement C1q B chain) This gene encodes the B-chain polypeptide of serum complement subcomponent C1q, which associates with C1r and C1s to yield the first component of the serum complement system. C1q is composed of 18 polypeptide chains which include 6 A-chains, 6 B-chains, and 6 C-chains. Each chain contains an N-terminal collagen-like region and a C-terminal C1q globular domain. C1q deficiency is associated with lupus erythematosus and glomerulonephritis. [provided by RefSeq, Dec 2016]
C1QB Gene-Disease associations (from GenCC):
  • C1Q deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.789

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
C1QBNM_001378156.1 linkc.91G>A p.Gly31Arg missense_variant Exon 2 of 3 ENST00000509305.6 NP_001365085.1
C1QBNM_000491.5 linkc.97G>A p.Gly33Arg missense_variant Exon 2 of 3 NP_000482.3 P02746A0A024RAB9
C1QBNM_001371184.3 linkc.91G>A p.Gly31Arg missense_variant Exon 3 of 4 NP_001358113.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
C1QBENST00000509305.6 linkc.91G>A p.Gly31Arg missense_variant Exon 2 of 3 1 NM_001378156.1 ENSP00000423689.1 D6R934

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152074
Hom.:
0
Cov.:
32
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000478
AC:
12
AN:
251078
AF XY:
0.0000663
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000528
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000363
AC:
53
AN:
1461802
Hom.:
0
Cov.:
32
AF XY:
0.0000385
AC XY:
28
AN XY:
727204
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.0000224
AC:
1
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26124
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000378
AC:
42
AN:
1111984
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.514
Heterozygous variant carriers
0
4
8
13
17
21
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152192
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74402
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41512
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67992
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
May 08, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 33 of the C1QB protein (p.Gly33Arg). This variant is present in population databases (rs764348361, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with C1QB-related conditions. ClinVar contains an entry for this variant (Variation ID: 1443928). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Possibly Damaging". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

C1Q deficiency 2 Uncertain:1
Mar 25, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.19
BayesDel_addAF
Benign
-0.032
T
BayesDel_noAF
Uncertain
-0.050
CADD
Benign
20
DANN
Uncertain
0.99
DEOGEN2
Benign
0.17
.;T;T;T
Eigen
Benign
-0.58
Eigen_PC
Benign
-0.66
FATHMM_MKL
Benign
0.70
D
LIST_S2
Benign
0.26
T;T;T;T
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.79
D;D;D;D
MetaSVM
Uncertain
0.64
D
MutationAssessor
Pathogenic
3.2
.;.;.;M
PhyloP100
1.7
PrimateAI
Benign
0.35
T
PROVEAN
Pathogenic
-5.0
D;N;N;N
REVEL
Uncertain
0.49
Sift
Benign
0.043
D;D;D;D
Sift4G
Benign
0.079
T;D;D;D
Polyphen
0.69
.;.;.;P
Vest4
0.38, 0.36
MutPred
0.63
.;.;.;Gain of solvent accessibility (P = 0.0584);
MVP
0.95
MPC
1.4
ClinPred
0.93
D
GERP RS
2.5
Varity_R
0.054
gMVP
0.88
Mutation Taster
=94/6
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs764348361; hg19: chr1-22986046; API