22-35617214-C-G

Position:

• chr22-35617214-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The ENST00000397326.7(MB):​c.44G>C​(p.Trp15Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,872 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: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MB ENST00000397326.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.60

Genes affected

MB (HGNC:6915): (myoglobin) This gene encodes a member of the globin superfamily and is predominantly expressed in skeletal and cardiac muscles. The encoded protein forms a monomeric globular haemoprotein that is primarily responsible for the storage and facilitated transfer of oxygen from the cell membrane to the mitochondria. This protein also plays a role in regulating physiological levels of nitric oxide. Multiple transcript variants encoding distinct isoforms exist for this gene. [provided by RefSeq, May 2020]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.974

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MB	NM_005368.3	c.44G>C	p.Trp15Ser	missense_variant	1/3	ENST00000397326.7	NP_005359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MB	ENST00000397326.7	c.44G>C	p.Trp15Ser	missense_variant	1/3	1	NM_005368.3	ENSP00000380489.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461872 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727238

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 07, 2023

The c.44G>C (p.W15S) alteration is located in exon 2 (coding exon 1) of the MB gene. This alteration results from a G to C substitution at nucleotide position 44, causing the tryptophan (W) at amino acid position 15 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.47	T;T;T;T;T;T;T;.
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.95	.;D;.;.;D;.;D;D
M_CAP	Pathogenic	0.35	D
MetaRNN	Pathogenic	0.97	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.3	M;M;M;M;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-13	D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D;D;.
Polyphen		1.0	D;D;D;D;.;.;.;.
Vest4		0.91
MutPred		0.80		Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);Gain of glycosylation at W15 (P = 0.0056);
MVP		0.98
MPC		0.89
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.99
gMVP		0.95

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

Other links and lift over

dbSNP: rs374212851; hg19: chr22-36013261;