rs587778518

Variant names:

• chr1-43340015-C-CCTGG
• rs587778518
• NM_005373.3:c.744_747dupTGGC

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PP5_Moderate

The NM_005373.3(MPL):​c.744_747dupTGGC​(p.Asn250TrpfsTer13) variant causes a frameshift change. The variant allele was found at a frequency of 0.0000161 in 1,614,098 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. N250N) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: MPL NM_005373.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 4.28

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 1-43340015-C-CCTGG is Pathogenic according to our data. Variant chr1-43340015-C-CCTGG is described in ClinVar as [Pathogenic]. Clinvar id is 134831.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MPL	NM_005373.3	c.744_747dupTGGC	p.Asn250TrpfsTer13	frameshift_variant	Exon 5 of 12	ENST00000372470.9	NP_005364.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MPL	ENST00000372470.9	c.744_747dupTGGC	p.Asn250TrpfsTer13	frameshift_variant	Exon 5 of 12	1	NM_005373.3	ENSP00000361548.3
MPL	ENST00000413998.7	c.723_726dupTGGC	p.Asn243TrpfsTer13	frameshift_variant	Exon 5 of 12	1		ENSP00000414004.3
MPL	ENST00000638732.1	n.744_747dupTGGC		non_coding_transcript_exon_variant	Exon 5 of 10	1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152210 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000797 AC: 2 AN: 250948 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135610

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 SAS 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: 0.0000164 AC: 24 AN: 1461888 Hom.: 0 Cov.: 32 AF XY: 0.0000193 AC XY: 14 AN XY: 727246

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: 0.0000207

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152210 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74364

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Essential thrombocythemia;C1327915:Congenital amegakaryocytic thrombocytopenia Pathogenic:1

Aug 28, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Asn250Trpfs*13) in the MPL gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in MPL are known to be pathogenic (PMID: 8073287, 11133753). This variant is present in population databases (rs587778518, 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: 134831). For these reasons, this variant has been classified as Pathogenic. -

not specified Other:1

Sep 19, 2013

ITMI

Significance: not provided

Review Status: no classification provided

Collection Method: reference population

- -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs587778518; hg19: chr1-43805686;