INTRODUCTION: The preauricular sinus (PAuS) is a malformation of the auricula pinna. The structure may present isolated or as a component of a number of oto-renal syndromes. AIM: The aim of this study was to establish the incidence of PAuS in a Bulgarian cohort and propose a model for its inheritance, based on the transgenerational mechanisms derived from the genealogic trees of interviewed individuals. MATERIALS AND METHODS: A total of 100 healthy individuals were prospectively evaluated for the presence of a PAuS on a random cohort sampling principle. A descriptive statistical approach was used when categorizing the individual features. Individuals were also assessed in terms of their genealogies and presence of renal symptoms. RESULTS: Of all assessed individuals, 3% (n=3) had a structure complying with the criteria for a PAuS. No one having the structure reported renal symptoms. The genealogical trees were characteristic of a dominant trait with incomplete penetrance. CONCLUSION: The incidence of PAuS in our study cohort is similar to that of other Caucasian cohorts and gives a rare modern glimpse into the transgenerational inheritance of the PAuS, together with data on the oto-nephrological syndromes.