Hb Lake Tapawingo [α46(CE4)Phe→Ser; HBA2:c.140T>C]: A New Unstable α Chain Hemoglobin Variant Associated with Low Systemic Arterial Saturation

Department of Pediatrics, Division of Hematology/Oncology, Children's Mercy Hospital and Clinics, Kansas City, Missouri 64108, USA.
Hemoglobin (Impact Factor: 0.79). 08/2011; 35(4):411-6. DOI: 10.3109/03630269.2011.598986
Source: PubMed


A new unstable α-globin variant was detected in a child with hypoxemia and anemia. The child's mother was found to carry the same mutation. The hemoglobin (Hb) variant co-eluted with Hb A(2) by cation exchange high performance liquid chromatography (HPLC) and appeared cathodal to Hb A and anodal to Hb F by isoelectric focusing. It represented less than 20% of the total Hb and was unstable by isopropanol testing. Gene sequencing identified a missense mutation on the α2 gene [HBA2:c.140T>C]. Oxygen dissociation and P(50) test results were normal.

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