Diamond-Blackfan Anemia 12

A number sign (#) is used with this entry because of evidence that Diamond-Blackfan anemia-12 (DBA12) is caused by heterozygous mutation in the RPL15 gene (604174) on chromosome 3p24. One such patient has been reported.

Description

Diamond-Blackfan anemia (DBA) is an inherited red blood cell aplasia that usually presents in the first year of life. The main features are normochromic macrocytic anemia, reticulocytopenia, and nearly absent erythroid progenitors in the bone marrow. Patients show growth retardation, and approximately 30 to 50% have craniofacial, upper limb, heart, and urinary system congenital malformations. The majority of patients have increased mean corpuscular volume, elevated erythrocyte adenosine deaminase activity, and persistence of hemoglobin F. However, some DBA patients do not exhibit these findings, and even in the same family, symptoms can vary between affected family members (summary by Landowski et al., 2013).

For a discussion of genetic heterogeneity of DBA, see DBA1 (105650).

Molecular Genetics

Landowski et al. (2013) studied 87 probands diagnosed with DBA on the basis of normochromic, often macrocytic anemia; reticulocytopenia; a low number or lack of erythroid precursors in bone marrow; and, in some patients, congenital malformations and elevated erythrocyte adenosine deaminase activity. All patients had previously been screened by Sanger sequencing and were negative for mutation in the 10 DBA-associated ribosomal protein genes; array CGH for copy number variation revealed large deletions in 6 probands, including 1 in the RPL15 gene in a female patient who was diagnosed with anemia at birth and responded to corticosteroid treatment, remaining in remission for 6 years. She also had a ventricular septal defect and triphalangeal thumbs.