Genetic Variant CYB5R3:c.734-1G>T (chr22-42619946-C-A) – ACMG Classification: Likely_pathogenic (7 pts)

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PVS1_StrongPM2PP5

The NM_000398.7(CYB5R3):c.734-1G>T variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (no stars).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.0 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

CYB5R3
NM_000398.7 splice_acceptor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic no assertion criteria provided P:1

Conservation

PhyloP100: 7.81

Publications

0 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

CYB5R3 links:

ENSG00000289517 (HGNC:):

ENSG00000289517 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 2.3245034 fraction of the gene.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 22-42619946-C-A is Pathogenic according to our data. Variant chr22-42619946-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 238.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYB5R3	NM_000398.7 link	c.734-1G>T		splice_acceptor_variant, intron_variant	Intron 8 of 8	ENST00000352397.10	NP_000389.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYB5R3	ENST00000352397.10 link	c.734-1G>T		splice_acceptor_variant, intron_variant	Intron 8 of 8	1	NM_000398.7	ENSP00000338461.6
ENSG00000289517	ENST00000617178.5 link	n.269-1G>T		splice_acceptor_variant, intron_variant	Intron 3 of 13	1		ENSP00000482500.2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

Data not reliable, filtered out with message: AC0

AF:

0.00

AC:

AN:

1443006

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

716212

African (AFR)

AF:

0.00

AC:

AN:

33098

American (AMR)

AF:

0.00

AC:

AN:

42468

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25674

East Asian (EAS)

AF:

0.00

AC:

AN:

38756

South Asian (SAS)

AF:

0.00

AC:

AN:

83420

European-Finnish (FIN)

AF:

0.00

AC:

AN:

51732

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5754

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1102488

Other (OTH)

AF:

0.00

AC:

AN:

59616

GnomAD4 genome

Cov.:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

LINK: link

Submissions by phenotype

METHEMOGLOBINEMIA, TYPE II

Pathogenic:1

Oct 05, 1992

OMIM

Significance:Pathogenic

Review Status:no assertion criteria provided

Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.62

BayesDel_noAF

Pathogenic

0.32

CADD

Pathogenic

(source)

DANN

Uncertain

0.99

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.91

FATHMM_MKL

Pathogenic

0.98

PhyloP100

7.8

GERP RS

4.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Mutation Taster

=0/100

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.95

SpliceAI score (max)

1.0

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.39

Position offset: 50

DS_AL_spliceai

1.0

Position offset: -1

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

Publications

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Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over