Molecular sex identification of dry human teeth specimens from Sokoto, Northwestern Nigeria

Abstract

Background:The advent of molecular techniques has revolutionized the ability of scientists to estimate the sex of individuals. Forensic odontology plays an important role in establishing the sex of victims with bodies mutilated beyond recognition due to major disaster. The genetic difference between males and females is defined by the presence or absence of the Y-chromosome. The use of alphoid-repeat primers in sex estimation was first applied on dried blood. Generally, the X, Y alphoid repeats blind test attest to the accuracy of genetic testing, and also point the potential for occasional error in morphometric sexing.Aim:To estimate genetic sex of dry human teeth specimens from Sokoto, Northwestern Nigeria, using polymerase chain reaction (PCR).Materials and Methods:A single-blind study of DNA analysis for sex estimation of nine dry human teeth specimens from Sokoto, Northwestern Nigeria, through PCR, using alphoid repeats primers, was undertaken.Results:The genetic sex of each group of the teeth samples were accurately (100%) identified. For each group of teeth, PCR Sensitivity = 100%, Specificity = 0%, Predictive value of positive test = 100%, Predictive value of negative test = 0%, False positive rate = 0%, False negative rate = 0%, Efficiency of test = 100%. Fisher's exact probability test P = 1. Z-test: z- and P values were invalid.Conclusion:This study has demonstrated the successful use of alphoid-repeat primers in genetic sex identification of human dry teeth samples from Sokoto, Northwestern Nigeria. This is the first known study estimating the sex of human dry teeth specimens by means of PCR in Nigeria. There is need for further studies in Nigeria to complement the findings of this study.

Molecular Technique for Gender Identification: A Boon in Forensic Odontology

“…Also sex determination was successfully achieved through analysis of dental hard tissue in the carcasses of 2 bodies kept under water for about one year and approximately eleven years wherein the pulp tissues had been dissolved and lost [42]. Zagga et al studied molecular sex determination on dry teeth specimens from cadaveric, primary and permanent teeth samples using alphoid repeat primers and obtained 100% result [52].…”

“…Almost 90% of the amel gene transcripts are articulated from the X-chromosome while the remaining from the Ychromosome [56]. The X and Y copies of amelogenin gene do not undertake recombination that is correlative, and that is why, it is the most favored genetic marker for gender assessment in current scenario [52]. Nakahori et al sequenced Amelogenin gene for the very first time [57].…”

Identification of Amelogenin Gene on Burnt Teeth Samples through Nested Polymerase Chain Reaction Amplification for Sex Identification

“…Teeth are considered the most suitable sample for DNA analysis of sex identification from fragmented, highly decomposed and burnt corpses as they are highly mineralized and highly resistant to heat and decomposition (Zagga et al 2014). The DNA in tooth is also preserved in the sealed pulp cavity and protected from harsh environmental conditions , making it a reliable source for sex determination even after decomposition.…”