rs779132175

Positions:

chr1-43346804-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_005373.3(MPL):c.1178C>T(p.Thr393Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

MPL
NM_005373.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 4.19

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MPL	NM_005373.3 linkuse as main transcript	c.1178C>T	p.Thr393Ile	missense_variant	8/12	ENST00000372470.9	NP_005364.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MPL	ENST00000372470.9 linkuse as main transcript	c.1178C>T	p.Thr393Ile	missense_variant	8/12	1	NM_005373.3	ENSP00000361548	P1	P40238-1
MPL	ENST00000413998.7 linkuse as main transcript	c.1157C>T	p.Thr386Ile	missense_variant	8/12	1		ENSP00000414004
MPL	ENST00000638732.1 linkuse as main transcript	n.1178C>T		non_coding_transcript_exon_variant	8/10	1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251196

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135822

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000447

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:

0.00000180

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000756

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Primary myelofibrosis;C1327915:Congenital amegakaryocytic thrombocytopenia;C3275998:Thrombocythemia 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Aug 30, 2021

- -

Congenital amegakaryocytic thrombocytopenia

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Nov 11, 2019

- -

Essential thrombocythemia;C1327915:Congenital amegakaryocytic thrombocytopenia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 01, 2023

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 393 of the MPL protein (p.Thr393Ile). This variant is present in population databases (rs779132175, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with MPL-related conditions. ClinVar contains an entry for this variant (Variation ID: 576320). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on MPL protein function. 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

Benign

0.20

BayesDel_addAF

Benign

-0.048

BayesDel_noAF

Benign

-0.13

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.49

T;.

Eigen

Uncertain

0.60

Eigen_PC

Uncertain

0.60

FATHMM_MKL

Uncertain

0.86

LIST_S2

Benign

0.73

T;T

M_CAP

Benign

0.079

MetaRNN

Uncertain

0.66

D;D

MetaSVM

Uncertain

0.18

MutationAssessor

Benign

1.8

L;.

MutationTaster

Benign

0.73

N;N

PrimateAI

Benign

0.47

PROVEAN

Benign

-2.1

N;.

REVEL

Uncertain

0.58

Sift

Benign

0.085

T;.

Sift4G

Uncertain

0.013

D;.

Polyphen

1.0

D;.

Vest4

0.57

MutPred

0.67

Loss of catalytic residue at T393 (P = 0.1002);.;

MVP

0.91

MPC

0.77

ClinPred

0.85

GERP RS

5.2

Varity_R

0.10

gMVP

0.42

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over