Age estimation in dental pulp DNA based on human telomere shortening

Iliyenko

EUREKA: Health Sciences

et al. 2017

Objective of research. To analyze features of stomatological status indexes, relative length of telomeres and phenotype of immunocompetent cells of peripheral blood in children with chronological enamel hypoplasia – residents of Ukrainian territories, contaminated with radionuclides after the Chornobyl NPP accident. Materials and methods. The object of research is chronological enamel hypoplasia (CEH) of permanent teeth, and lymphocytes of peripheral blood (PB). The subject of research is the state of oral cavity hygiene, caries intensity, gingivitis severity degree, relative telomere length (RTL), and phenotype of immunocompetent cells (ICC) of peripheral blood (PB). Methods of the research: stomatological, immunological (flow cytofluorometry), molecular genetic (fluorescence in situ hybridization-flow cytometry – flow-FISH), statistical. Results. Two types of the analysis of the stomatologic status, RTL and phenotype of PB ICC were carried out: the first is the comparison of indexes of the combined group of children with anamnesis complicated by radiation (group No. 1 with CEH + group No. 2 without CEH) comparing with the control group No. 3; the second is the analysis of indeces of the group No. 1 comparing with the same markers in children of the groups No. 2 and No. 3. The first stage of the analysis shows thesignificant worsening of oral hygien indices , high DMFTand DMFS in children with permanent dentition, higher degree of gums inflamation and moresignificant RTL shortening in children of the combined group (No. 1 + No. 2) comparing with the control. Changes of the same character, but more expressed observed during the another analysis concerning the children with anamnesis complicated by radiation and CEH comparing with the control. Reliable changes in the content of PB ICC subpopulations in the examined children of all groups were not identified. Conclusions. 1. Inchildren with CEH, complicated by ionizing radiation (IR) influence in low doses diapason the highest degree of stomatological status disorders comparing with the examined reference and control groups was determined: unsatisfactory and poor oral cavity hygiene according to OHI-S (1.76±0.41, р˂0.0001 and р˂0.0001, respectively) and Silness-Loe index (1.73±0.45, р˂0.0001 and р˂0.0001, respectively); very high intensity of dental caries ((DMFT=7.0±2.29, р=0.003and р˂0.0001; DMFS=8.74±2.58, р=0.0004 and р˂0.0001, respectively); mean degree of gingivitis severity (РМА 47.55±14.27 %, р˂0.0001 and р˂0.0001, respectively). 2. At CEH, which occurs due to the complex of negative factors during first years of life, including IR in residents of territories with effective doses more than 1.0 mSv/year, reliable shortening of relative telomeres length of PB lymphocytes comparing with the control group (15.17±3.20, р=0.0002) was found. Reliable differences in the content of peripheral blood immunocompetent cells when compared the examined groups were not identified. 3. Results of indices of the groups No. 1, No. 2 and No. 3 comparison are agreed with the data, obtained in result of dispersive analysis that allowed to separate the most informative indices concerning stomatological examination of children: OHI-S index (F=34.92; р˂0.001); Silness-Loe index (F=27.01; р˂0.001); dft+DMFT (F=82.23; р˂0.001); dfs+DMFS (F=49.41; р˂0.001); DMFT (F=13.94; р˂0.001); DMFS(F=19.41; р˂0.001); РМА (F=41.25; р˂0.001); RTL (F=7.53; р=0.001).

supporting

confidence: 75%

Section: Introductionmentioning

confidence: 99%

Features of Stomatologic Status, Telomere Lengths and Phenotype of Immunocompetent Cells of Peripheral Blood in Children – Residents of Ukrainian Territories, Contaminated With Radionuclides

Iliyenko

EUREKA: Health Sciences

et al. 2017

American Journal of Biochemistry and Biotechnology

“…Meanwhile, others used the Terminal Restriction Fragments (TRF) length method to measure the TL, as Tsuji et al (2002) and Takasaki et al (2003) in Japan; r = -0.832 and -0.749 respectively and p<0.01. Ren et al (2009) in China who recorded a correlation coefficient "r" value = -0.913 and p<0.01, Hewakapuge et al (2008) explained the differences in the observed "r" values as a result of differences in ethnicity, sample size, laboratory conditions in each study and not be due to differences in measuring TL in different methods.…”

Section: Discussionmentioning

confidence: 99%

“…As a result, it is difficult to determine age by existing data. In addition, there is no research report of systemic population about telomere shortening (Takasaki et al, 2003;Ren et al, 2009). Saeed et al (2012) confirmed that it is necessary to design basic science experiments for better evaluation of the role of TL in molecular prediction of biological age, as it remains the most promising biomarker for this purpose.…”

Section: Introductionmentioning

confidence: 99%

Telomere Length Measurement by Quantitative Real-time PCR: A Molecular Marker for Human Age Prediction

Alhusseini¹,

Madboly²

2016

The fact that telomere shortening occurs with aging leads to the hypothesis that a correlation could be made between Telomere Length (TL) and suspect age. This study aimed to assess if TL can be used as an investigational tool to predict human age through developing a formula based on this correlation with accuracy suitable to be applied in forensic practice. A quantitative real-time PCR study was carried out on 80 Egyptians, ranging in age from 1-79 years. The results confirmed that the relative TL significantly shortened with aging; "r" = -0.903 (p<0.001). The human age could be determined by the following formula: (Y = 66.9-28X), (Y: Age in years; X: Relative TL), with a regression analysis between relative TL and age had an R 2 = 0.815. The standard error of age estimate was ±10.14 years. The present study concluded that estimation of human age based on the relative TL measured by quantitative real-time PCR may be a useful method for age prediction, especially when there is no morphologic information in the biological samples, but the estimated standard error of age prediction in this study was quite high (±10 years) to be used with certainty in forensic investigations. Inter-individual variations in TL and variability among the gender must be also considered when applying this method. So, this method could only give a rough estimation of age and it may be a complementary method for age estimation from soft tissues.

“…It has been found that the length of telomeres decreases with age, presumably due to cell divisions -the more cell divisions, the shorter the telomere length -and, since the number of cell divisions increases with age, telomere length could be a proxy for age. 56 Indeed, several studies have shown this, [63][64][65][66] although telomere length is individual, and relies on genetic and environmental factors. The error given in studies is around ±10 years.…”

Section: Chemical and Molecular Biological Methodsmentioning

confidence: 99%

Age estimation of skeletal remains: principal methods

Villa¹,

Lynnerup²

2014

RRFMS

Abstract:The age of an individual is often a fundamental piece of data in connection with forensic identification of unidentified bodies. The methods most often used are based on visually determining various morphological, age-related changes in the skeleton (or teeth, although odontological methods are not reviewed in this paper). As such, these methods are all relative: ie, they do not obtain results in calendar years but estimates of the age at death, often with a rather large range. Recently, methods have been proposed for more direct ascertainment of age at death: eg, protein racemization and radiocarbon methods. The latter method, especially, may yield absolute age (year of birth), because radiocarbon activity (as measured in specific proteins in specific cells or tissues of the body) may be in equilibrium with the so-called bomb-pulse, when atmospheric radiocarbon content has changed markedly from one year to another. This review covers the basic and most often used gross morphological methods, radiologically-based methods, biochemical methods, and radiocarbon dating.