rs121965018

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PP3_StrongPP5

The NM_000398.7(CYB5R3):​c.719A>G​(p.Asp240Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000121 in 1,613,808 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00013 ( 0 hom. )

Consequence

CYB5R3
NM_000398.7 missense

Scores

13
5
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:2

Conservation

PhyloP100: 8.01

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 5 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.977
PP5
Variant 22-42623803-T-C is Pathogenic according to our data. Variant chr22-42623803-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 252.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CYB5R3NM_000398.7 linkc.719A>G p.Asp240Gly missense_variant Exon 8 of 9 ENST00000352397.10 NP_000389.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CYB5R3ENST00000352397.10 linkc.719A>G p.Asp240Gly missense_variant Exon 8 of 9 1 NM_000398.7 ENSP00000338461.6
ENSG00000289517ENST00000617178.5 linkn.254A>G non_coding_transcript_exon_variant Exon 3 of 14 1 ENSP00000482500.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152172
Hom.:
0
Cov.:
33
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:
0.0000597
AC:
15
AN:
251310
AF XY:
0.0000589
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000132
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000133
AC:
194
AN:
1461636
Hom.:
0
Cov.:
31
AF XY:
0.000132
AC XY:
96
AN XY:
727118
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53402
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.000163
AC:
181
AN:
1111820
Other (OTH)
AF:
0.000215
AC:
13
AN:
60378
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
12
24
35
47
59
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
152172
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68002
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
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:
0.0000731
Hom.:
0
Bravo
AF:
0.0000567
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.000109
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Deficiency of cytochrome-b5 reductase Pathogenic:1Uncertain:1
Jan 13, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 29, 2022
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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
Feb 16, 2024
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PP3, PM2_moderate, PM3, PS3_supporting -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.77
BayesDel_addAF
Pathogenic
0.37
D
BayesDel_noAF
Pathogenic
0.50
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.50
.;D;.;.;.
Eigen
Pathogenic
0.81
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.98
D;D;.;.;D
M_CAP
Pathogenic
0.49
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.1
.;M;.;.;.
PhyloP100
8.0
PrimateAI
Uncertain
0.64
T
PROVEAN
Pathogenic
-6.7
D;D;D;D;D
REVEL
Pathogenic
0.95
Sift
Uncertain
0.021
D;D;D;D;D
Sift4G
Uncertain
0.0040
D;D;D;D;D
Polyphen
1.0
.;D;.;.;.
Vest4
0.94
MVP
1.0
MPC
0.31
ClinPred
0.94
D
GERP RS
4.1
Varity_R
0.91
gMVP
0.82
Mutation Taster
=0/100
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: rs121965018; hg19: chr22-43019809; API