rs121965009

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000398.7(CYB5R3):​c.316G>A​(p.Val106Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000267 in 1,613,470 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

CYB5R3
NM_000398.7 missense

Scores

2
9
5

Clinical Significance

Uncertain significance criteria provided, single submitter P:1U:1

Conservation

PhyloP100: 7.88

Publications

7 publications found
Variant links:
Genes affected
CYB5R3 (HGNC:2873): (cytochrome b5 reductase 3) This gene encodes cytochrome b5 reductase, which includes a membrane-bound form in somatic cells (anchored in the endoplasmic reticulum, mitochondrial and other membranes) and a soluble form in erythrocytes. The membrane-bound form exists mainly on the cytoplasmic side of the endoplasmic reticulum and functions in desaturation and elongation of fatty acids, in cholesterol biosynthesis, and in drug metabolism. The erythrocyte form is located in a soluble fraction of circulating erythrocytes and is involved in methemoglobin reduction. The membrane-bound form has both membrane-binding and catalytic domains, while the soluble form has only the catalytic domain. Alternate splicing results in multiple transcript variants. Mutations in this gene cause methemoglobinemias. [provided by RefSeq, Jan 2010]
CYB5R3 Gene-Disease associations (from GenCC):
  • methemoglobinemia
    Inheritance: AR Classification: DEFINITIVE Submitted by: Illumina
  • methemoglobinemia due to deficiency of methemoglobin reductase
    Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • hereditary methemoglobinemia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CYB5R3NM_000398.7 linkc.316G>A p.Val106Met missense_variant Exon 4 of 9 ENST00000352397.10 NP_000389.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CYB5R3ENST00000352397.10 linkc.316G>A p.Val106Met missense_variant Exon 4 of 9 1 NM_000398.7 ENSP00000338461.6

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152212
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000281
AC:
7
AN:
249368
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000624
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:
0.0000355
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000233
AC:
34
AN:
1461140
Hom.:
0
Cov.:
31
AF XY:
0.0000234
AC XY:
17
AN XY:
726774
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.0000224
AC:
1
AN:
44634
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26110
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86018
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53356
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000297
AC:
33
AN:
1111712
Other (OTH)
AF:
0.00
AC:
0
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.465
Heterozygous variant carriers
0
4
8
11
15
19
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000591
AC:
9
AN:
152330
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74476
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41566
American (AMR)
AF:
0.00
AC:
0
AN:
15304
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68022
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000347
Hom.:
0
Bravo
AF:
0.0000416
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000412
AC:
5

ClinVar

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

Submissions by phenotype

METHEMOGLOBINEMIA, TYPE I Pathogenic:1
May 01, 2008
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

not provided Uncertain:1
Nov 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ClinVar contains an entry for this variant (Variation ID: 237). This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 106 of the CYB5R3 protein (p.Val106Met). This variant is present in population databases (rs121965009, gnomAD 0.004%). This missense change has been observed in individual(s) with methemoglobinemia (PMID: 1400360, 3680497; Invitae). This variant is also known as Val105Met. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CYB5R3 protein function. Experimental studies have shown that this missense change affects CYB5R3 function (PMID: 1400360). 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
Uncertain
0.45
BayesDel_addAF
Pathogenic
0.20
D
BayesDel_noAF
Pathogenic
0.23
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.0
.;T;.;.;.;T
Eigen
Uncertain
0.33
Eigen_PC
Uncertain
0.25
LIST_S2
Uncertain
0.92
D;D;.;.;D;D
M_CAP
Uncertain
0.17
D
MetaRNN
Uncertain
0.66
D;D;D;D;D;D
MetaSVM
Uncertain
0.30
D
MutationAssessor
Benign
0.0
.;L;.;.;.;.
PhyloP100
7.9
PrimateAI
Uncertain
0.77
T
PROVEAN
Benign
-1.7
N;N;N;N;N;N
Sift
Benign
0.084
T;T;T;T;T;T
Sift4G
Benign
0.12
T;T;T;T;T;.
Vest4
0.86
ClinPred
0.49
T
GERP RS
2.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.26
gMVP
0.70
Mutation Taster
=3/97
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs121965009; hg19: chr22-43026905; COSMIC: COSV106479505; COSMIC: COSV106479505; API