부산대학교 도서관

Hereditary persistence of fetal hemoglobin (HPFH) is characterized by increased levels of Hb F during adult life. Nondeletional forms of HPFH are characterized by single base mutations in the Aγ and Gγ promoters, resulting in an increase of Hb F ranging from 3 to 20% in heterozygotes. Many point mutations in this region have been described, including the Aγ −195 (C>G) mutation that causes the Brazilian type of HPFH (HPFH-B). To better understand this mechanism, we have developed HPFH-B transgenic mice. mRNA levels of human γ-globin of −195 transgenic mice were clearly higher when compared with control transgenic mice bearing a wild type sequence of the γ promoter. Thus, our data indicate that the −195 mutation is the unique cause of elevation of Hb F in Brazilian HPFH. These results could provide us with an opportunity to study the modifying effects of the Hb F in the phenotype of sickle cell disease and β-thalassemia (β-thal). [ABSTRACT FROM AUTHOR]