COMPARISON OF THE TOOTH SHAPE AND SIZE IN TABBY AND NON-TABBY MICE

Basic anatomical and embryological investigations of the dental disord er in tabby mice were performed some 20-30 years ago. In order to brid ge the gap in research activity in this field and as a prerequisite fo r future developmental studies, the dental characteristics of the tabb y mice were updated in a stock presently available. Qualitative and qu antitative parameters of the functional teeth were determined in 50 ma les and females of different phenotypes segregated from the stock of t abby mice. A parallel investigation was made in a common laboratory mo use (ICR stock). In ICR mice, the body weight was two times higher and this was reflected in the cheek teeth which were significantly larger (but similar in shape) when compared to the wild type non-tabby contr ols. Among tabby homozygous and hemizygous mice, at least one incisor was absent in 50% of females, and in 70% of males - where predominance of the right side was apparent. In these groups the mean length and w idth of the cheek teeth were significantly reduced compared to the cor responding wild type controls, despite similar body weight. Changes in crown pattern, including also reduction or absence of cusps, resulted in characteristic morphology of the cheek teeth. In contrast to the e arlier literature, duplication of an incisor or an explicit supernumer ary tooth in the cheek region were not found in the present tabby coll ection and the heterozygous specimens were less affected.