Characterization of a new alpha-thalassemia-1 deletion in a Spanish family.

A new type of alpha-thalassemia-1 was characterized in one Spanish patient with Hb H disease and in her mother. The restriction map of this deletion suggests that the deletion of 22 kb has occurred on a chromosome carrying a zeta-globin triplication. The resulting chromosome lacks the alpha 2- and alpha 1-globin genes, the psi alpha 2- and psi alpha 1-globin genes, and one of the three zeta-globin genes, while the other two zeta-globin genes and the theta 1-globin gene have been retained.