Forensic dentistry: The key to the truth

Introduction Human organism can be identified through testing and analysis of DNA sequences. The most common source of DNA for analysis is blood, soft tissues, hair, bones and teeth. Teeth represent a tissue of choice for analysis in those cases where there is high degree of degradation of other tissues. Hard tooth structure provides protection and preservation of DNA molecules. The aim was to investigate which group of teeth and dental tissue (pulp or hard dental tissues) has the greatest amount of DNA. Material and method Forty-five extracted teeth were analyzed. In the first examination 30 teeth were divided into the three groups (10 teeth each): first group were incisors, second premolars and third molars. The teeth were measured before and after the procedure of DNA isolation using special scale with precision of 0.02-0.000005ng. The procedure included grinding teeth in a blender and DNA isolation using commercial kits (isolation with magnetic particles). For the second test 15 teeth divided into two groups were used. In the first group isolation of DNA molecules was performed from pulp tissue, and in the second group from hard dental tissues. The quantification of samples was done with Quantifiler® Duo DNA Quantification Kit by Applied Biosystems. Results The greatest amount of DNA was obtained from molars (0.230011ng/μl/g) while the smallest amount of DNA was obtained from incisors and it was 0.06437ng/μl/g. In addition, the amount of DNA isolated from pulp tissue was significantly greater than that from hard dental tissues (pulp of molars obtained quantitatively the largest amount of DNA). Conclusion Main tissue to be used for the isolation of DNA from a tooth is pulp, but in those cases when it is not present (endodontic treatment), hard dental tissues provide sufficient quantity of DNA for identification procedures. The group of teeth that provides the greatest amount of DNA is molars

Evaluation of APOE Genotype and Vascular Risk Factors As Prognostic and Risk Factors for Alzheimer’s Disease and Their Influence On Age of Symptoms Onset

BACKGROUND: Alzheimer’s disease (AD), the most common cause of dementia, is evolving to become a threatening epidemy of the 21st century. Only 21% of the predicted number of AD patients in Macedonia have been diagnosed and treated, which means that almost 80% are underdiagnosed or misdiagnosed. Apolipoprotein E gene (APOE) is recognised as the strongest genetic risk factor for sporadic AD. Whether and when Alzheimer’s disease develops, depends on the very complex interaction between genetic and modifiable risk factors. It has been known that vascular factors like hypertension, diabetes mellitus, hypercholesterolemia and obesity increase the risk of developing both AD, vascular dementia and mixed AD and vascular pathology AIM: This study aims to evaluate the influence of APOEε4 allele presence and modifiable vascular risk factors (hypertension, diabetes mellitus and dyslipidemia) as prognostic and risk factors for AD and their influence on the age of onset of AD symptoms among 144 AD patients from Macedonia. MATERIAL AND METHODS: Study group of a total of 144 patients diagnosed with AD was evaluated. APOE genotyping was performed using APOE haplotype-specific sequence specific-primer (SSP)-PCR (Polymerase Chain Reaction) methodology. The non-standardized questionnaire was used to obtain information about demographics, lifestyle and modifiable risk factors that could influence disease onset and phenotype. RESULTS: Statistically significant association was found between the presences of APOEε4 allele in AD group versus controls. The presence of APOEε4 allele increases the risk of developing AD in a 3-fold manner. The average age of disease onset in the ε4 carrier group was 67.2 ± 8.3 and in the ε4 non-carrier group 69.7 ± 9.4. This confirms that the presence of APOEε4 allele shifts towards earlier disease onset, though the difference is not statistically significant. Out of the vascular risk factors, only hypertension was significantly associated with earlier AD onset. Out of total 144 patients, in 22.9% the first symptom onset was before the age of 65, that can be considered as early onset Alzheimer’s Disease (EOAD), which is much higher than 5% for EOAD as most of the studies report. CONCLUSIONS: The average age of disease onset of 68.4 years could be considered earlier than the average age of AD onset worldwide. Out of all the vascular risk factors analysed in this study, only hypertension and dyslipidemia were found to significantly increase the risk for developing AD and only the presence of hypertension influences the age of onset, shifting towards earlier disease onset. Public awareness campaigns should be organised to influence general population knowledge about Alzheimer’s disease, early recognition and the influence of modifiable vascular risk factors