Triple heterozygosity of a hemoglobin variant: hemoglobin Pyrgos with other hemoglobinopathies.
This article is the first report of hemoglobin (Hb) Pyrgos along with other Hbs forming triple-heterozvgous patterns. Of 2 cases, the first occurred in a Thai girl with thalassemic facies, marked anemia, and hepatosplenomegaly, who had Hb Pyrgos in association with Hb H disease with Hb Constant Spring (CS). This case represents a triple heterozygosity comprising Hb Pyrgos, alpha-thalassemia 1, and Hb CS. Hb electrophoresis revealed an abnormal Hb in addition to Hbs CS, A2, A, Bart's, and H. This abnormal Hb moved slightly faster than Hb A but more slowly than Hb Bart's. Polymerase chain reaction revealed that the abnormal Hb was caused by a missense mutation within codon 83 of the beta-globin gene (GGC to GAC) resulting in a glycine-to-aspartic acid substitution, which corresponds to Hb Pyrgos. The patient required blood transfusions by the age of 3 years. A splenectomy was performed when she was 5 years old, after which her hematocrit level remained above 32%. The second case was the patient's older sister who was also triple heterozygous (Hb Pyrgos, E, and CS) but was healthy.
Jetsrisuparb
Arunee
A
Department of Pediatrics, Faculty of Medicine, Faculty of Associated Medical Sciences, Khon Kaen University, Thailand. arunee@pediatrician.com
Sanchaisuriya
Kanokwan
K
Fucharoen
Goonnapa
G
Fucharoen
Supan
S
Wiangnon
Surapon
S
Komwilaisak
Patcharee
P
D000483:Alleles; D019943:Amino Acid Substitution; D000745:Anemia, Hemolytic, Congenital / Q000235:genetics* / Q000601:surgery / Q000628:therapy; D001797:Blood Protein Electrophoresis; D001803:Blood Transfusion; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D004252:DNA Mutational Analysis; D004588:Electrophoresis, Cellulose Acetate; D005260:Female; D005914:Globins / Q000235:genetics*; D006446:Hemoglobin E / Q000235:genetics*; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D020125:Mutation, Missense; D010375:Pedigree; D017354:Point Mutation; D013156:Splenectomy; D017085:alpha-Thalassemia / Q000150:complications / Q000235:genetics*
D006455:Hemoglobins, Abnormal; C073730:hemoglobin Pyrgos; D005914:Globins; D006446:Hemoglobin E; C030448:hemoglobin Bart's; C035541:Hemoglobin Constant Spring