t(4;9)(q21.22;p24) SEC31A/JAK2

2017-04-01   Julie Sanford Biggerstaff 

1.Idaho Cytogenetics Diagnostic Laboratory, Boise, ID 83706, USA; biggersj@slhs.org

Abstract

Review on t(4;9)(q21.22;p24) SEC31A/JAK2, with data on clinics, and the genes involved.

Clinics and Pathology

Phenotype stem cell origin

Hodgkin and Reed-Sternberg cells, which derive from pre-apoptotic crippled germinal center (GC) B-cells, are positive for CD30, CD15, CD40 and IRF4/MUM1

Epidemiology

Hodgkin lymphoma itself is common, but this particular translocation may be rare within the disorder. However, it is not often assayed for; found in 2/131 cHL cases examined: a M/31 with nodular sclerosis cHL, alive 60 mths after diagnosis; and a M/83 with lymphocyte-depleted cHL who died at day 14 (Van Roosbroeck et al, 2011).

Treatment

SEC31A/JAK2 acts as a constitutively activated tyrosine kinase and is sensitive to JAK2 inhibition

Prognosis

Yet unknown.

Genes Involved and Proteins

Gene name
SEC31A (SEC31 homolog A, COPII coat complex component)
Location
4q21.22
Dna rna description
gene is 72,606 bp with 25 exons; transcribed from the - strand; coding region is 62,863 bp with 24 exons
Protein description
1166 amnio acids. Protein transport protein SEC31A is ubiquitously expressed and forms part of the coat protein complex II (COPII) which is comprised of at least four other proteins in addition to SEC31A this complex is involved in formation of transport vesicles from the ER to Golgi. Protein localized to the cytoplasmic side of the cell membrane and is GTP-dependent.
Gene name
JAK2 (janus kinase 2)
Location
9p24.1
Dna rna description
143,098 bp with 24 exons; transcribed from the + strand; coding region is 104,804 bp with 23 exons.
Atlas Image
Protein description
Protein is 1132 amino acids with multiple functional domains; regulated by auto-phosphorylation. Non-receptor protein tyrosine kinase, ubiquitously expressed.
Germinal mutations
Germline mutations associated with autosomal dominant Familial Thrombocythemia
Somatic mutations
Gain of Function V617F mutation and mutations in exon 12 of the gene common in patients with Polycythemia Vera, Myelofibrosis with Myeloid Metaplasia or idiopathic erythrocytosis.

Result of the Chromosomal Anomaly

Note

Fusion results in 5 SEC31A fused to 3 partner gene JAK2

Description

Exon 22 SEC31A is fused with exon 17 of JAK2 in the two reported cases (Van Roosbroeck et al, 2011)

Detection protocole

FISH using JAK2 and SEC31A breakapart probes, rtPCR or RNAseq.

Oncogenesis

The fusion protein is a constitutively activated tyrosine kinase: JAK2 activation is mediated by a domain region of SEC31A that lies between the WD-40-like and proline-rich domains of the protein (Van Roosbroeck et al, 2011).

Bibliography

Pubmed IDLast YearTitleAuthors
107884762000Mammalian homologues of yeast sec31p. An ubiquitously expressed form is localized to endoplasmic reticulum (ER) exit sites and is essential for ER-Golgi transport.Tang BL et al
213251692011JAK2 rearrangements, including the novel SEC31A-JAK2 fusion, are recurrent in classical Hodgkin lymphoma.Van Roosbroeck K et al

Summary

Fusion gene

SEC31A/JAK2

Citation

Julie Sanford Biggerstaff

t(4;9)(q21.22;p24) SEC31A/JAK2

Atlas Genet Cytogenet Oncol Haematol. 2017-04-01

Online version: http://atlasgeneticsoncology.org/haematological/1682/t(4;9)(q21-22;p24)

External Links