Gene frequencies of hemoglobin Constant Spring and hemoglobin Paksé in Phayao Province

Abstract

Hemoglobin Constant Spring (Hb CS) and Hb Paksé are abnormal Hbs caused by mutations at the stop codon of  a2 globin gene. Compound heterozygous of these genes with a-thalassemia 1 can lead to severe Hb H disease. To determine the magnitude of problem with this disease in Phayao province, we have examined gene frequency of Hb CS and Hb Paksé in the population. A total of 1,307 subjects were studied by allele specific polymerase chain reaction. Of these 1,307 subjects, 634 were healthy individuals, 353 were general patients and 320 were pregnant women and their husbands who were attended at several hospitals in Phayao province. Hb CS and Hb Paksé genes were identified in 137 (10.5 %) and 4 (0.31 %) subjects, respectively. These included 106 heterozygous Hb CS, 19 homozygous Hb CS, 12 compound heterozygous Hb CS / a-thalassemia 1 (SEA), 2 heterozygous Hb Paksé and 2 homozygous Hb Paksé. Gene frequencies for Hb CS and Hb Paksé in Phayao population were calculated to be 0.0597 and 0.0023, respectively. With a relatively high frequency of Hb CS and the existence of  Hb Paksé in Phayao population, it is conceivable that severe Hb H disease should not be uncommon among this population. The data should also prove useful in a prevention and control program of severe thalassemia diseases in the area.

Keywords:          Hb Constant Spring,         Hb Paksé,             Hb H disease