Helen Bishara, “Measurement of Purines in Cichlid Fish”
Mentor: Phillip Owens, Mathematics & Natural Sciences
Oral Presentation Block 1 

This study aims to identify the molecules responsible for a unique color trait of a new breed of bony fish. Recently two species of genus Labeotropheus were cross-bread, producing hybrid offspring males that showed a unique color trait. Upon research of the novel color trait, it was discovered that the unique color was associated with an increased ability to reflect ultraviolet light. The molecules guanine and hypoxanthine are known to reflect light in other closely related breeds of Cichlid fish. These purines are usually present in iridophore (pigment) cells in the skin. In this project, we have extracted purines from the iridophores that were isolated from both the novel fish breed and from normal colored fish. By measuring the guanine and hypoxanthine content of the extracts we can determine if there is a higher level of purines in the novel fish pigments. The pigments are collected from shed fish scales and isolated into extracts. Spectrophotometric analysis of each extract is then completed and compared to an analysis of hypoxanthine and guanine solutions. Paper chromatography is then performed to further verify the presence of each purine and also to identify the presence of any other unknown molecules in the iridophores.