1-43346804-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PM2

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

9
10

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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM1
In a domain Fibronectin type-III 2 (size 94) in uniprot entity TPOR_HUMAN there are 5 pathogenic changes around while only 2 benign (71%) in NM_005373.3
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
MPLNM_005373.3 linkuse as main transcriptc.1178C>T p.Thr393Ile missense_variant 8/12 ENST00000372470.9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
MPLENST00000372470.9 linkuse as main transcriptc.1178C>T p.Thr393Ile missense_variant 8/121 NM_005373.3 P1P40238-1
MPLENST00000413998.7 linkuse as main transcriptc.1157C>T p.Thr386Ile missense_variant 8/121
MPLENST00000638732.1 linkuse as main transcriptn.1178C>T non_coding_transcript_exon_variant 8/101

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251196
Hom.:
0
AF XY:
0.0000147
AC XY:
2
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:
4
AN:
1461888
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
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.:
32
Bravo
AF:
0.00000756
ExAC
AF:
0.0000165
AC:
2

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 submitterclinical testingFulgent Genetics, Fulgent GeneticsAug 30, 2021- -
Congenital amegakaryocytic thrombocytopenia Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Nov 11, 2019- -
Essential thrombocythemia;C1327915:Congenital amegakaryocytic thrombocytopenia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingInvitaeNov 01, 2023This 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
T
BayesDel_noAF
Benign
-0.13
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.49
T;.
Eigen
Uncertain
0.60
Eigen_PC
Uncertain
0.60
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Benign
0.73
T;T
M_CAP
Benign
0.079
D
MetaRNN
Uncertain
0.66
D;D
MetaSVM
Uncertain
0.18
D
MutationAssessor
Benign
1.8
L;.
MutationTaster
Benign
0.73
N;N
PrimateAI
Benign
0.47
T
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
D
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.

Other links and lift over

dbSNP: rs779132175; hg19: chr1-43812475; API