The Congenital Dyserythropoietic Anemia Registry (CDAR)

To establish and maintain a CDA registry (CDAR): a comprehensive registry of subjects with
the diagnosis of any type of congenital dyserythropoietic anemia in North America. Subjects
and their physicians have expressed interest in participating in a national/international
registry that could promote research and further understanding of this rare disease-group.

CDAs consist a heterogeneous group of rare genetic disorders causing ineffective
erythropoiesis with the characteristic finding of multinuclear erythroid precursors in the
bone marrow. The other hematopoietic lineages seem unaffected. The diagnosis of CDA is
clinically challenging and is based on identifying the characteristic morphology of
erythroblasts in the bone marrow of subjects presenting with chronic anemia, frequently with
evidence of hemolysis but suboptimal reticulocytosis, and iron overload. Three types are
well-defined by marrow morphology, although a recent classification recognizes seven
different genetic types. Since certain gene defects were identified in the different types of
CDAs, our understanding of the biology and pathogenesis of these diseases has been improving.
However, many gaps still exist in our understanding of the related molecular mechanisms
primarily due to the rarity of the disease and the lack of systematic approach to study these
subjects. In addition, the heterogeneity observed among subjects and the clinical overlap
with other hematologic disorders, namely hemolytic anemias with brisk erythropoietic response
that may be associated with erythroid dysplasia, and with ineffective erythropoiesis, further
complicates the diagnosis and often delays appropriate diagnosis and therapy.

The purpose of CDAR will be to establish a database and bio-repository for CDA subjects and
their families in order to systematically study this rare disease-group. Data regarding these
subjects will be collected confidentially at initial presentation or diagnosis and
periodically thereafter over a long period of time (>15 years). In addition, blood, bone
marrow and/or DNA samples of enrolled subjects will be stored for research studies with the
aim to improve our understanding, diagnosis, and treatment of CDA.

Inclusion Criteria:

- Diagnosis of Congenital Dyserythropoietic Anemia (CDA), whether a genetic mutation is
identified or not

- Evidence of congenital anemia/jaundice or a positive family history

- Evidence of ineffective erythropoiesis

- Typical morphological appearance of bone marrow erythroblasts

- All ages (ages 0-99)

Exclusion Criteria:

- Diagnosis of cancer

- Myelodysplasia

- Secondary dyserythropoiesis: e.g.; vitamin B12 deficiency or drug-related.

Note1: Patients with rare band 3 (SLC4A1) mutations recently described to be associated
with dyserythropoiesis will be eligible since the mechanisms appear to involve direct
participation of band 3 in the erythroblast mitosis and cytokinesis.

Note2: Siblings, parents, and family members of patients with confirmed CDA diagnosis are
encouraged to participate in the study.