Inclusion Criteria:

* Suspected (e.g., persistent unexplained cytopenia, circulating peripheral blasts etc.) MDS or MDS/MPN overlap disorders and undergoing diagnostic work-up with planned bone marrow assessments, or diagnosed with de novo or therapy-related MDS within 12 months of enrollment per the World Health Organization (WHO) criteria1 and undergoing clinical evaluation and planned bone marrow assessments to confirm MDS or to evaluate disease status
* Bone marrow aspirate expected to be performed within 1 week of registration, and in all cases must be performed no later than 4 weeks after enrollment
* Age 18 or older
* If anemic without prior MDS diagnosis, B12 level, serum folate, mean corpuscular volume (MCV), red cell distribution width (RDW), ferritin, and iron studies (Iron, total iron-binding capacity (TIBC) test, and percent saturation) must be performed within prior 6 months.

Exclusion Criteria:

* Prior treatment for MDS at entry and through the time of the entry bone marrow aspirate
* Treatment with hematopoietic growth factors in prior 6 months
* Diagnosis of a solid tumor or hematologic malignancy within two years prior to enrollment except for in situ cancer of the skin (basal or squamous cell), cervix, bladder, breast, or prostate
* Treatment with radiation therapy in the two years prior to registration
* Non-hormonal treatment for malignancy within the two years prior to registration
* Established hereditary bone marrow failure syndrome
* Known primary diagnosis of aplastic anemia, classical paroxysmal nocturnal hemoglobinuria, amegakaryocytic thrombocytopenic purpura, or large granular lymphocyte leukemia
* Enrolled in the Connect® MDS/AML Disease Registry (NCT01688011)