rs368753117

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PP2PP3_Moderate

The NM_005373.3(MPL):​c.212G>A​(p.Arg71Gln) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000155 in 1,613,634 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R71W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

MPL
NM_005373.3 missense, splice_region

Scores

3
16
Splicing: ADA: 0.9998
2

Clinical Significance

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

Conservation

PhyloP100: 3.70

Publications

3 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, Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen
  • congenital amegakaryocytic thrombocytopenia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
  • 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 25 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Gene score misZ: 0.39478 (below the threshold of 3.09). Trascript score misZ: 1.6963 (below the threshold of 3.09). GenCC associations: The gene is linked to hereditary isolated aplastic anemia, congenital amegakaryocytic thrombocytopenia, thrombocythemia 2, congenital amegakaryocytic thrombocytopenia 1, familial thrombocytosis.
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MPLNM_005373.3 linkc.212G>A p.Arg71Gln missense_variant, splice_region_variant Exon 2 of 12 ENST00000372470.9 NP_005364.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MPLENST00000372470.9 linkc.212G>A p.Arg71Gln missense_variant, splice_region_variant Exon 2 of 12 1 NM_005373.3 ENSP00000361548.3
MPLENST00000413998.7 linkc.191G>A p.Arg64Gln missense_variant, splice_region_variant Exon 2 of 12 1 ENSP00000414004.3
MPLENST00000638732.1 linkn.212G>A splice_region_variant, non_coding_transcript_exon_variant Exon 2 of 10 1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152164
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000799
AC:
2
AN:
250418
AF XY:
0.00000738
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461352
Hom.:
0
Cov.:
33
AF XY:
0.0000151
AC XY:
11
AN XY:
726998
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33464
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86244
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53282
Middle Eastern (MID)
AF:
0.000184
AC:
1
AN:
5440
European-Non Finnish (NFE)
AF:
0.0000126
AC:
14
AN:
1112002
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60362
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000394
AC:
6
AN:
152282
Hom.:
0
Cov.:
32
AF XY:
0.0000537
AC XY:
4
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41542
American (AMR)
AF:
0.00
AC:
0
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.550
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000547
Hom.:
0
Bravo
AF:
0.0000416
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

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
Mar 10, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Congenital amegakaryocytic thrombocytopenia Uncertain:1
Nov 11, 2019
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Essential thrombocythemia;C1327915:Congenital amegakaryocytic thrombocytopenia Uncertain:1
Jan 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 71 of the MPL protein (p.Arg71Gln). This variant also falls at the last nucleotide of exon 2, which is part of the consensus splice site for this exon. This variant is present in population databases (rs368753117, gnomAD 0.002%). 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: 458371). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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
0.086
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.43
CADD
Pathogenic
26
DANN
Uncertain
0.99
DEOGEN2
Benign
0.31
T;.
Eigen
Benign
-0.18
Eigen_PC
Benign
0.033
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.77
T;T
M_CAP
Benign
0.018
T
MetaRNN
Benign
0.17
T;T
MetaSVM
Benign
-0.91
T
MutationAssessor
Benign
0.0
N;.
PhyloP100
3.7
PrimateAI
Benign
0.34
T
PROVEAN
Benign
0.20
N;.
REVEL
Benign
0.10
Sift
Benign
0.62
T;.
Sift4G
Uncertain
0.029
D;.
Polyphen
0.17
B;.
Vest4
0.090
MVP
0.76
MPC
0.27
ClinPred
0.31
T
GERP RS
4.7
PromoterAI
-0.021
Neutral
Varity_R
0.051
gMVP
0.61
Mutation Taster
=61/39
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
1.0
SpliceAI score (max)
0.48
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.48
Position offset: 0

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

Publications

Other links and lift over

dbSNP: rs368753117; hg19: chr1-43803902; API