LOGISTIC ANALYSIS OF THE EFFECTS OF SHOVEL TRAIT ON CARABELLIS TRAIT IN A MONGOLOID POPULATION

Mongoloid populations differ from Caucasoids by having a high prevalen ce of shovel trait and a low prevalence of Carabelli's trait. This stu dy was conducted to investigate the effects ofthe shovel trait on Cara belli's trait in a Mongoloid population. The research design sought a population that resides in an isolated area and exhibits low admixture with neighboring populations. The Mongoloid group selected for study was the Bunun tribe of aborigines who inhabit an alpine area in Taiwan . The effects of sex and age on Carabelli's trait were controlled in t his investigation, as was the association between tooth size and Carab elli's trait. Results show that males were more likely to have Carabel li's trait expressed on teeth than females, The buccolingual diameter of Carabelli's trait teeth was larger than that of teeth without the t rait. After adjusting for sex, age, and tooth size, the existence of t he shovel trait increased the likelihood of having Carabelli's trait b y a factor of three, an effect that is significant. (C) 1996 Wiley-Lis s, Inc.