Deryni - Genetic Basis of Deryni Powers

Genetic Basis of Deryni Powers

The basic ability to naturally develop Deryni powers is hereditary in nature, passing from parent to child and thus from generation to generation. Although several characters in the novels refer to Deryni-nonDeryni hybrids as "half-breeds" or "half-Deryni," the inherent nature of Deryni powers enables them to be passed to a child even if only one parent is Deryni. (Throughout the novels and ancillary material, nonDeryni humans are referred to simply as "humans," although it is unspecified whether this exclusionary terminology was originally positive or negative.) However, the natural strength of the Deryni bloodline tends to become weakened if succeeding generations continue to breed with full-blooded humans. The exact rate of this genetic "dilution" is not specified, and several half-Deryni characters (such as Alaric Morgan and Duncan McLain) display significant levels of arcane strength. An appendix to one of the early books speculates that the usual Deryni powers are carried on the X-chromosome (thus explaining why Morgan and Duncan, who have Deryni mothers, can have full powers), while the "Haldane potential" (also seen in several other families), is carried on the Y-chromosome. However, this is not borne out by later genealogies and seems to have been dropped as an explanation by Katherine Kurtz.

In addition to their genetic basis, most Deryni abilities must be trained and developed. While basic arcane skills can be often be mastered during adolescence, more complex abilities and talents may require constant study and practice throughout the adult life of a Deryni. Deryni adepts such as Camber MacRorie and Wencit Furstán of Torenth continue their arcane studies throughout their lives, enabling them to wield powers far beyond the abilities of many of their contemporaries. Conversely, Queen Jehana of Gwynedd, a full-blooded Deryni from an ancient and powerful lineage, is barely able to perform the most basic of Deryni talents, due to her lack of training throughout much of her life. Regardless of the inherent strength of a Deryni's natural powers, proper training is essential for those powers to be of any practical use.

It should also be noted that the use of the Deryni powers generally requires some degree of mental concentration and is physically tiring to perform. The need for concentration is key to the drama of the battle that ends in Duncan's capture in 'The King's Justice, as well as his rescue later in the same book. Alaric Morgan is frequently shown pushing himself to the point of exhaustion and collapse by the repeated use of his powers in short periods of time, generally when driven by the demands of events. These facts, together with the training requirement, impose realistic limits on Deryni magic.