Haematologica 2003; 88:(03) ECR08
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THE FIRST CASE OF A COMPOUND HETEROZYGOSITY FOR HB E-SASKATOON AND HB S
Stamatia Theodoridou, Eleni Plata, Photini Karababa, Afroditi Loutradi, Timoleon Vyzantiadis, Anna Manitsa
Correspondence: Stamatia Theodoridou, M.D.; Hemoglobinopathy Prevention Unit, “Hippokration” Hospital of Thessaloniki, Constantinoupoleos 49, Thessaloniki 54642, Greece. Tel: 2310 892042 Fax: 2310 843000.

Hemoglobin E-Saskatoon (b22-Glu->Lys) was first described by Vella et al.1 in a Canadian woman of mixed Scotish and Dutch origin and ever since the variant has been found in Greece, Scotland, Spain and Turkey.2-6 Hb E-Saskatoon seems to be an innocuous variant but there are not any available data concerning the association of haemoglobin E-Saskatoon with other haemoglobinopathies. Few published data exist concerning compound heterozygosity of b-Thalassemia and Hb E-Saskatoon.4-7 All cases are mild and with haematological features of a common thalassemia trait.
We report the first case of a compound heterozygosity for HbS and Hb E-Saskatoon in a four-year old Greek girl. Carriers of haemoglobin E-Saskatoon were also found to be, her mother, brother, grand father and uncle. They all come from a village in Northern Greece.
The hematologic data of the propositus were: Hb=12,8 g/dL, Hct=37,8%, RBC=4980x103/mL, MCV=75,8 fl, MCH=25,7 pg. The blood films showed hypochromia, microcytosis, anisocytosis. Electrophoresis revealed a variant with electrophoretic properties of Hb E and Hb S. The sickle test was positive. Hemoglobin HPLC (Variant, Biorad) (Figure 1) isolation revealed the presence of Hb F, Hb A, Hb A2, Hb S (45,7%) and of an unknown variant (42,6%) eluting before S.
DNA studies that included gene amplification using the polymerase chain reaction (PCR), DGGE electrophoresis, DNA sequencing (Figure 2) and ASO hybridization showed a compound heterozygosity for Hb S and E-Saskatoon.
The propositus is a healthy girl with normal development, without pains and until now asymptomatic. The mildness of the condition was evident in the hemoglobin E-Saskatoon heterozygotes of the same family. In the literature there are few cases of compound heterozygosity for haemoglobin S and E8,9 reported to be symptomatic. This compound heterozygosity is the first description in Greece and in literature.

Key Words: Hb E-Saskatoon, Hb S, Hemoglobinopathies

Figure 1. HPLC isolation of S and E-Saskatoon hemoglobins.

Figure 2. DNA sequencing.

REFERENCES

  1. Vella F, Lorkin PA, Carrell RW, Lehmann H. A new haemoglobin variant resembling Hb E. Haemoglobin E-Saskatoon: (b22Glu-Lys). Canad J Biochem 1967;45:1385-91.
  2. Kaltsoya A, Ballas A, Sofroniadou K, Fessas Ph. A mild beta thalassemia haemoglobin E disease. Fifth Congress of the Asian and Pacific Society of Hematology. Instanbul, 1969, Abstract book: 40.
  3. Tills D, Muir V, Warlow A, Hopkinson DA, Lorkin PA, El-Harmi MA et al. The occurrence of Hb E-Saskatoon in Scotland. Hum Genet 1976; 33:179-80.
  4. Fessas Ph. Compound heterozygosity for Hb E-Saskatoon and b-thalassemia. Hemoglobin 1991; 345-6.
  5. Gonzalez Redondo JM, Sicilia A, Murga MJ, Kutlar A, Wilson JB, Huisman TH. Hb E-Saskatoon or alpha 2 beta 2(22)(B4)Glu----Lys in a Spanish family. Hemoglobin 1987;11:35-8
  6. Birden E, Oner C, Gumruk F, Gurgey A, Altay C. Homozygosity for Hb E-Saskatoon [beta22 (b4)Glu_Lys] in a Turkish patient. Hemoglobin 2001 Nov; 25:409-15.
  7. Gurgey A, Sipahioglu M, Aksoy M. Compound heterozygosity for Hb E-Saskatoon or alpha 2 beta 2(22)(B4)Glu----Lys and beta-thalassemia type IVS-I-6 (T----C). Hemoglobin 1990; 14:449-51.
  8. Weatheral DJ, Clegg JB. The thalassaemia syndromes. Blackwell Oxford U.K 2001.
  9. Gupta R, Jarris M, Yardumian A. Compound heterozygosity for haemoglobin S and haemoglobin E. British J Haematol 2000; 108:463.