Mehmet Akif Çürük

Hb H (β4) Disease in Çukurova, Southern Turkey

In this study, 32 patients with Hb H (β4) disease have been identified. Three different α-thalassemia-1 (thal) determinants; nine with the −17.4 kb (MED I) type, 12 with the −20.5 kb type and 10 with the −26.5 kb (MED II) type were characterized. Of the 32 patients, 19 had the 3.7 kb deletion and one had the 4.2 kb deletion in trans to α-thal-1 determinants. Only one patient, homozygous for the polyadenylation signal (poly A) site (PA 1) mutation, was identified to be associated with Hb H disease. The other patient had the poly A (PA 1) mutation in trans to the MED I (−17.4 kb) determinant. The 5 nt (nucleotide) deletion was present in three patients, two of them in the same family; this mutation was found in association with the MED II (26.5 kb deletion). The other patient had the −5 nt mutation in trans to the MED I (−17.4 kb) determinant. An unstable hemoglobin (Hb) variant [Hb Adana, codon 59 (C→A)] was present in association with the α‐thal-1 deletion (20.5 kb) in two adults and caused a severe type ...In this study, 32 patients with Hb H (β4) disease have been identified. Three different α-thalassemia-1 (thal) determinants; nine with the −17.4 kb (MED I) type, 12 with the −20.5 kb type and 10 with the −26.5 kb (MED II) type were characterized. Of the 32 patients, 19 had the 3.7 kb deletion and one had the 4.2 kb deletion in trans to α-thal-1 determinants. Only one patient, homozygous for the polyadenylation signal (poly A) site (PA 1) mutation, was identified to be associated with Hb H disease. The other patient had the poly A (PA 1) mutation in trans to the MED I (−17.4 kb) determinant. The 5 nt (nucleotide) deletion was present in three patients, two of them in the same family; this mutation was found in association with the MED II (26.5 kb deletion). The other patient had the −5 nt mutation in trans to the MED I (−17.4 kb) determinant. An unstable hemoglobin (Hb) variant [Hb Adana, codon 59 (C→A)] was present in association with the α‐thal-1 deletion (20.5 kb) in two adults and caused a severe type of Hb H disease. Five patients with Hb H disease had the genotype – –MED II/αPA 2α one had a Hb S heterozygosity (– –MED II/αPA 2α + Hb AS). A patient with Hb H disease (– –MED I/−α3.7) also had Hb S trait.

Two rare hemoglobin variants in the Çukurova Region of Turkey: Hb E-Saskatoon and Hb G-Coushatta.

Hb E-Saskatoon and Hb G-Coushatta are rare hemoglobin variants that are not a health problem. Herein we present a Turkish woman that was diagnosed as homozygous Hb E-Saskatoon (only the second such case reported from Turkey) and a Turkish boy diagnosed as heterozygote Hb E-Saskatoon. Additionally, 2 Turkish sisters diagnosed as heterozygote Hb G-Coushatta are presented.

Preliminary Data on Preimplantation Genetic Diagnosis for Hemoglobinopathies in Turkey

Hemoglobinopathies are the most common genetic diseases in Turkey. Sickle cell anemia is prevalent in the Çukurova region but β-thalassemia (thal) is seen all over the country. The incidence of sickle cell trait is 10% and β-thal trait is 3.7% in this region. The families at risk for hemoglobinopathies have come to our center for prenatal diagnosis since 1992. In 15 years, 1,593 fetuses were examined. Four hundred and ten fetuses were found to be homozygous or compound heterozygous for sickle cell anemia and β-thal. Some mothers had affected fetuses several times. Preimplantation genetic diagnosis (PGD) is an option to avoid the termination of a pregnancy. Studies for PGD of sickle cell anemia were done at Çukurova University Hospital, Çukurova, Adana, Turkey.