Double Heterozygous CDAN1 Variants of Uncertain Significance Associated With a Phenotype Consistent With Congenital Dyserythropoietic Anemia Type 1.

Congenital dyserythropoietic anemia is a group of hereditary disorders characterized by erythroid hyperplasia and ineffective erythropoiesis, resulting in anemia of varying severity. Congenital dyserythropoietic anemia Type 1 (CDA-1) is classically associated with biallelic mutations in the CDAN1 gene. Here, we report the first case of compound heterozygous CDAN1 mutations p.(D1043V) and p.(S1036F) in clinical practice, presenting in a 24-year-old woman with mild, asymptomatic macrocytic anemia and hyperferritinemia. These variants are currently classified as variants of uncertain significance; however, this report represents the first clinical case of this compound heterozygous CDAN1 variant combination in a patient with a phenotype consistent with CDA-1. As the phenotypic boundaries of CDA-1 continue to expand, clinicians should consider CDA-1 in the differential diagnosis of unexplained macrocytic anemia, even in the absence of severe anemia.