Absence of triradius d in a three-generation pedigree and other variations of main-line D



An example is reported of a rare dermatoglyphic variant (absence of triradius d) in a woman of mixed European and Cherokee American Indian ancestry. This variant was not present in her parents, her five siblings, four nephews or one niece. Attention is drawn to the continuum from an absent triradius d to a triradius with an abbreviated main-line associated with either an open field in interdigital area IV, or a loop in interdigital area IV or a tented arch at d. This same continuum occurs at c. The absent triradius at d is extremely rare and the tented arch at d is very rare.