1-43338146-C-T

Variant names:

Variant summary

Our verdict is Pathogenic. The variant received 20 ACMG points: 20P and 0B. PVS1PS3PP5_Very_Strong

The NM_005373.3(MPL):c.127C>T(p.Arg43*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,614,058 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 Pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000914406: Savoia et al. (2007) demonstrated that platelet surface expression of other glycoproteins was normal in one individual carrying the variant but MPL expression was scarcely detectable. Serum TPO levels were elevated and in colony-forming unit assays, platelet c-MPL and bone marrow colonies were reduced. Savoia et al. (2007)" and additional evidence is available in ClinVar. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

MPL
NM_005373.3 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:11

Conservation

PhyloP100: 1.90

Publications

9 publications found

Variant links:

Genes affected

MPL (HGNC:7217): (MPL proto-oncogene, thrombopoietin receptor) In 1990 an oncogene, v-mpl, was identified from the murine myeloproliferative leukemia virus that was capable of immortalizing bone marrow hematopoietic cells from different lineages. In 1992 the human homologue, named, c-mpl, was cloned. Sequence data revealed that c-mpl encoded a protein that was homologous with members of the hematopoietic receptor superfamily. Presence of anti-sense oligodeoxynucleotides of c-mpl inhibited megakaryocyte colony formation. The ligand for c-mpl, thrombopoietin, was cloned in 1994. Thrombopoietin was shown to be the major regulator of megakaryocytopoiesis and platelet formation. The protein encoded by the c-mpl gene, CD110, is a 635 amino acid transmembrane domain, with two extracellular cytokine receptor domains and two intracellular cytokine receptor box motifs . TPO-R deficient mice were severely thrombocytopenic, emphasizing the important role of CD110 and thrombopoietin in megakaryocyte and platelet formation. Upon binding of thrombopoietin CD110 is dimerized and the JAK family of non-receptor tyrosine kinases, as well as the STAT family, the MAPK family, the adaptor protein Shc and the receptors themselves become tyrosine phosphorylated. [provided by RefSeq, Jul 2008]

MPL Gene-Disease associations (from GenCC):

thrombocythemia 2
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
congenital amegakaryocytic thrombocytopenia
Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae)
congenital amegakaryocytic thrombocytopenia 1
Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
familial thrombocytosis
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
hereditary isolated aplastic anemia
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

MPL links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 20 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PS3

PS3 evidence extracted from ClinVar submissions: SCV000914406: Savoia et al. (2007) demonstrated that platelet surface expression of other glycoproteins was normal in one individual carrying the variant but MPL expression was scarcely detectable. Serum TPO levels were elevated and in colony-forming unit assays, platelet c-MPL and bone marrow colonies were reduced. Savoia et al. (2007); SCV005402191: Colony assays have shown a notable decrease in the total number of colony-forming cells from congenital amegakaryocytic thrombocytopenia I patients carrying this variant and other nonsense mutations compared to those from healthy donors (PMID: 16470591). In addition, an expression analysis conducted on hematopoietic progenitor cells revealed a lack of CD110 expression in patients harboring this variant, as well as in individuals with other nonsense or frameshift mutations and mutations predicted to result in complete splice site loss (PMID: 32703794).

PP5

Variant 1-43338146-C-T is Pathogenic according to our data. Variant chr1-43338146-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 371574.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005373.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MPL	NM_005373.3	MANE Select	c.127C>T	p.Arg43*	stop_gained	Exon 2 of 12	NP_005364.1	P40238-1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
MPL	ENST00000372470.9	TSL:1 MANE Select	c.127C>T	p.Arg43*	stop_gained	Exon 2 of 12	ENSP00000361548.3	P40238-1
MPL	ENST00000413998.7	TSL:1	c.106C>T	p.Arg36*	stop_gained	Exon 2 of 12	ENSP00000414004.3	Q5JUY5
MPL	ENST00000638732.1	TSL:1	n.127C>T		non_coding_transcript_exon	Exon 2 of 10

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152170

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000318

AC:

AN:

251424

AF XY:

0.0000294

show subpopulations

Gnomad AFR exome

AF:

0.000185

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000352

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000150

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.0000151

AC XY:

AN XY:

727246

show subpopulations

African (AFR)

AF:

0.0000597

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86256

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000171

AC:

AN:

1112008

Other (OTH)

AF:

0.0000166

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.466

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000329

AC:

AN:

152170

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74344

show subpopulations

African (AFR)

AF:

0.000121

AC:

AN:

41424

American (AMR)

AF:

0.00

AC:

AN:

15284

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5188

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10618

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68038

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.555

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.0000334

Hom.:

Bravo

AF:

0.0000491

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000412

AC:

ClinVar

ClinVar submissions

Significance:Pathogenic

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

Congenital amegakaryocytic thrombocytopenia (2)

Congenital amegakaryocytic thrombocytopenia 1 (2)

MPL-related disorder (2)

not provided (2)

Essential thrombocythemia;C1327915:Congenital amegakaryocytic thrombocytopenia (1)

Primary myelofibrosis;C3275998:Thrombocythemia 2;C5882667:Congenital amegakaryocytic thrombocytopenia 1 (1)

Thrombocythemia 2 (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.41

BayesDel_noAF

Pathogenic

0.59

CADD

Pathogenic

(source)

DANN

Uncertain

1.0

Eigen

Pathogenic

0.81

Eigen_PC

Pathogenic

0.69

FATHMM_MKL

Uncertain

0.78

PhyloP100

1.9

Vest4

0.90

GERP RS

4.8

PromoterAI

-0.00070

Neutral

(source)

Mutation Taster

=0/200

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.070

Details are displayed if max score is > 0.2

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over