We describe the case of a 17-year-old male presenting with features of nontuberculous mycobacterial infection, pulmonary fibrinoid granulomatous vasculitis, and myelodysplasia in the setting of a pathogenic GATA2 frameshift mutation confirmed by next-generation sequencing.
Genetic predispositions to myeloid malignancies can be classified into three categories: familial cancer syndromes associated with increased risk of various malignancies including myelodysplasia and acute myeloid leukemia such as Li-Fraumeni syndrome and constitutional mismatch repair deficiency (CMMRD); germline mutations conferring a specific increased risk of myelodysplastic syndrome and acute myeloid leukemia such as mutations in ANKRD26, CEBPA, DDX41, ETV6, GATA2, RUNX1, SRP72 genes; and finally primarily pediatric inherited bone marrow failure syndromes such as Fanconi anemia, dyskeratosis congenita, severe congenital neutropenia, Shwachman-Diamond syndrome and Diamond Blackfan anemia.
GATA2 mutations are associated with several conditions, including Emberger syndrome which is the association of primary lymphedema with hematological anomalies and an increased risk for myelodysplasia and leukemia.
To identify acquired somatic mutations associated with myeloid transformation in patients with GATA2 mutations, we sequenced the region of the ASXL1 gene previously associated with transformation from myelodysplasia to myeloid leukemia.
Though the disease-causing mutations commonly occur in the GATA-2 DNA binding domain, we identified a patient with mycobacterial infection and myelodysplasia who had an uncharacterized heterozygous deletion in a GATA2 cis-element consisting of an E-box and a GATA motif.
GATA-2 anomaly and clinical phenotype of a sporadic case of lymphedema, dendritic cell, monocyte, B- and NK-cell (DCML) deficiency, and myelodysplasia.
We also found mutations in genes seldom reported in inherited BMF (IBMF), such as <i>SAMD9</i> and <i>SAMD9L</i> (N = 16 of the 86 patients, 18.6%), <i>MECOM/EVI1</i> (N = 6, 7.0%), and <i>ERCC6L2</i> (N = 7, 8.1%), each of which was associated with a distinct natural history; <i>SAMD9</i> and <i>SAMD9L</i> patients often experienced transient aplasia and monosomy 7, whereas <i>MECOM</i> patients presented early-onset severe aplastic anemia, and <i>ERCC6L2</i> patients, mild pancytopenia with myelodysplasia.
The t(3;21)(q26.2;q22) translocation is a rare chromosomal abnormality exhibited almost exclusively in therapy-related myelodysplastic syndrome/acute myeloid leukemia (t-MDS/AML) or in the blastic crisis phase of chronic myelogenous leukemia, which results in the fusion of the runt related transcription factor 1 (<i>RUNX1</i>, also called <i>AML1</i>) gene at 21q22 to the myelodysplasia syndrome 1 (<i>MDS1</i>)-ecotropic virus integration site 1 (<i>EVI1</i>) complex locus (<i>MECOM</i>) at 3q26.2, generating various fusion transcripts, including <i>AML1/MDS1/EVI1</i> (<i>AME</i>).
The other child did not develop MDS despite expansion of a clone with a single insertion in the myelodysplasia syndrome 1 (MDS1) gene and was cured by early standard allo-HSCT.
Development of a dual-color, double fusion FISH assay to detect RPN1/EVI1 gene fusion associated with inv(3), t(3;3), and ins(3;3) in patients with myelodysplasia and acute myeloid leukemia.
The EVI-1 gene encodes a Zn finger, DNA binding protein previously detected in some acute myelogenous leukemias (AML) and myelodysplasias (MDS), but not in normal marrow or cord blood cells.
The EVI1 gene may be expressed through at least two pathways in hematologic malignancies; one is related to chromosomal changes at 3q26, while the other is related to myelodysplasia regardless of chromosomal changes at 3q26 region.
In summary, the results show that the defects in the erythroid development in a subpopulation of patients with myelodysplasia is localized at an early stage of the erythroid differentiation and is associated with the persistent expression of the CD34 antigen and, in some cases, with the expression of Evi-1.
Our results showed that EVI1 expression was frequent in patients with post-MDS AML and AML with trilineage myelodysplasia, regardless of the presence or absence of 3q26 abnormalities.
Genetic predispositions to myeloid malignancies can be classified into three categories: familial cancer syndromes associated with increased risk of various malignancies including myelodysplasia and acute myeloid leukemia such as Li-Fraumeni syndrome and constitutional mismatch repair deficiency (CMMRD); germline mutations conferring a specific increased risk of myelodysplastic syndrome and acute myeloid leukemia such as mutations in ANKRD26, CEBPA, DDX41, ETV6, GATA2, RUNX1, SRP72 genes; and finally primarily pediatric inherited bone marrow failure syndromes such as Fanconi anemia, dyskeratosis congenita, severe congenital neutropenia, Shwachman-Diamond syndrome and Diamond Blackfan anemia.
We found that blast phase of PV was characterized by overt myelodysplasia (n = 51, 88%); moderate to severe myelofibrosis (33 of 45, 73%); an abnormal karyotype (n = 51, 88%) that was often complex karyotype (n = 42, 72%); and gene mutations involving TP53 (55%), TET2 (27%), and DNMT3A (25%).
The t(3;21)(q26.2;q22) translocation is a rare chromosomal abnormality exhibited almost exclusively in therapy-related myelodysplastic syndrome/acute myeloid leukemia (t-MDS/AML) or in the blastic crisis phase of chronic myelogenous leukemia, which results in the fusion of the runt related transcription factor 1 (<i>RUNX1</i>, also called <i>AML1</i>) gene at 21q22 to the myelodysplasia syndrome 1 (<i>MDS1</i>)-ecotropic virus integration site 1 (<i>EVI1</i>) complex locus (<i>MECOM</i>) at 3q26.2, generating various fusion transcripts, including <i>AML1/MDS1/EVI1</i> (<i>AME</i>).
Mutations of RUNX1 have been reported to be associated with familial platelet disorder and with a predisposition for myelodysplasia and/or acute myeloid leukemia.
One is a complex t(15;21)(q24;q22), with both breakpoints mapped at the nucleotide level, joining RUNX1 to SIN3A and UBL7-AS1 in a patient with myelodysplasia.