First Description of Hb San Diego (HBB: c.328G>A) in a Chinese Family with Congenital Erythrocytosis

Abstract

Congenital erythrocytosis is a rare and hereditary disorder of red blood cell (RBC) production that can be caused by high oxygen affinity hemoglobin (Hb) variants. We applied a genetic approach including whole exome sequencing and Sanger sequencing. We identified a heterozygous β-globin gene (Hb San Diego or HBB: c.328G>A) in exon 3 as a causative germline mutation in a Chinese family with congenital erythrocytosis. We concluded that in erythrocytosis with a dominant inheritance and normal or inappropriately high erythropoietin (EPO) levels, the high oxygen affinity Hb variants should be considered. In addition, as a tool for identification of mutations in congenital erythrocytosis, whole exome sequencing improves diagnostic accuracy and provides the opportunity for discovery of novel variants.

KEYWORDS:

• Erythrocytosis
• Hb San Diego
• hemoglobin (Hb) variants
• high oxygen affinity

Acknowledgments

We are grateful to our patients and their families for participating in this study.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.