Most discussions about thalassemia center on beta thalassemia and it's categories of major, intermedia and minor. More recently, minor is divided into minor and minima, with minima referring to thal trait carriers who experience few if any symptoms. Deletion and mutation would only be discussed in terms of why thal occurs and not in terms of specific mutations/deletions. Alpha is usually mentioned in terms of three gene deletion alpha (hemoglobin H disease), and HbH is compared to intermedia in beta thals. Four gene deleted alpha leads to miscarriage or death or stillborn or death at birth because no hemoglobin is produced. The alpha gene is more common in the world but because it takes three genes to cause HbH, most alphas have no problems as they typically carry only one or two alpha thal genes among their four Hb alpha genes.
The easiest way to explain thal would be to talk about the categories of beta (major, intermedia and minor) and then mention alpha in terms of HbH.