Heredity and Forensic Implications of Lip Prints among Indian Twins and Non-Twin Siblings: A Cheiloscopy Study

Objectives: This study aimed to assess the lip prints of Indian twins and non-twin siblings to evaluate the existence of heredity in the lip prints of these individuals.

Materials and methods: The study employed a blind, cross-sectional, quantitative approach with an inductive method and extensive direct observation. The sample consisted of 30 twins and 30 non-twin siblings, divided into three groups based on gender with 10 subjects in each subgroup. All participants were aged between 10 and 30 years and were instructed on the methods and techniques involved in the study.

Results: The lip prints of participants were recorded using dark-colored lipstick, bond paper, cellophane tape, and a brush, and were examined for lip thickness measurement (in mm), classification of lip commissures, and assessment of groove patterns. The findings were then analyzed to determine the pattern of lip prints among twins and non-twin siblings.

Conclusion: Cheiloscopy, the forensic investigation technique based on lip trace identification, could benefit from this study's findings as it explores the existence of heredity in lip prints of Indian twins and non-twin siblings.