Positional effect of cis/trans alpha globin gene deletions on the formation of “H” bodies

Normal individuals have four alpha-globin genes, two on each member of the chromosome 16 pair (alpha alpha/alpha alpha). The alpha-thalassemia trait phenotype associated with deletions of two alpha-genes can be either on the same chromosome, the cis type (alpha alpha/--), or on opposite chromosomes, the trans type (alpha-/alpha-). Traditionally, the observation on vitally stained smears of occasional cells containing "H" bodies has been used as …