Detection of Caprine-specific Nucleic Acid Sequences in Goat Milk Using Polymerase Chain Reaction.

CONFLICT OF INTEREST: none declared. INTRODUCTION: This study was carried out to evaluate PCR-based method for detection of DNA in goat milk. It utilized primers targeting the mitochondrial cytochrome -b (mtcyt-b) gene, which was used as a target DNA for PCR amplification. METHODS: For the specific identification of goat mtcyt-b gene, pair of primers (GSL1, GSR2), were used, which produced a 428 base pair (bp) PCR product from milk samples as well as from peripheral blood. Amplification products were visualized on ethidium bromide-stained agarose gels. RESULTS AND DISCUSSION: Amplification products were not detected when the PCR was applied to DNA from animal species including cattle, sheep, swine, camel, deer, horse, donkey, and human, which indicates that the 2 pairs of primers are specific for goat. CONCLUSION: DNA can be extracted from goat milk and would be advantageous in the variety of application such as species identification in milk and milk.

Skin color. Could it be a new fingerprint?

OBJECTIVE: To prove that the difference in human skin color can be used as a new fingerprint. METHODS: A cross-sectional descriptive study was conducted in the Faculty of Medicine, The National Ribat University, Khartoum, Sudan between January and June 2010. The study consists of 139 subjects, which includes 41 Sudanese identical twins (82 subjects), 50 subjects from the general population, and 7 Chinese. All subjects were free of skin lesions. Based on reflectance spectrophotometry, the skin color has been read for all subjects from the inner upper arm using the Medisun skin check. Visual judgment on color differences was carried out directly with 3 normal observers, and through digital photos. RESULTS: Skin color was found to be different in all subjects under the study depending on visual judgment, digital photos, and skin color readings. Differences in skin color were also found between different parts of the body (color map). Color intensity reading in the first twin was 4.010 +/- 0.5, and in the second twin was 3.89 +/- 0.44 with a significant difference (p=0.001). The general population sample showed significant differences in skin color from each other, and from the Chinese group (p=0.002). CONCLUSION: In this study, we found that skin color between identical twins is different, as well as in the whole population, and could be a new personal identification method, which needs further international studies.