RESUMO
BACKGROUND: Chronological age estimation is a challenging marker in the field of forensic medicine. The current study aimed to investigate the accuracy of signal joint T-cell receptor rearrangement excision circles (sjTRECs) quantification and telomere length measurement as methods for estimating chronological age. METHODS: Telomere length was estimated in the DNA derived from the buccal cells through estimating the telomeric restriction fragment (TRF) length using TeloTTAGGG Telomere Length Assay while the sjTRECs quantification was carried out on DNA isolated from the blood samples using qPCR. RESULTS: The TRF length was shortened with increased age (r = -0.722, p < 0.001). The sjTRECs were also decreased with increased age (r = -0.831, p < 0.001). Stronger coefficient and lower standard error of the estimate was obtained when multiple regression analysis for age prediction based on the values of both methods was applied (r = -0.876, p < 0.001).
Assuntos
Envelhecimento/genética , Bioensaio , DNA/genética , Medicina Legal/métodos , Receptores de Antígenos de Linfócitos T/genética , Homeostase do Telômero , Telômero , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Criança , Pré-Escolar , Feminino , Voluntários Saudáveis , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/química , Polimorfismo de Fragmento de Restrição , Análise de Regressão , Linfócitos T/metabolismoRESUMO
The sequences of mitochondrial DNA (mtDNA) control region were investigated in 101 unrelated individuals living in the northern region of Nile delta (Gharbia, N=55 and Kafrelsheikh, N=46). DNA was extracted from blood stained filter papers or buccal swabs. HV1, HV2 and HV3 were PCR amplified and sequenced; the resulted sequences were aligned and compared with revised Cambridge sequence (rCRS). The results revealed presence of total 93 different haplotypes, 86 of them are unique and 7 are shared haplotypes, the most common haplotype, was observed with a frequency, 2.97% of population sample. High mtDNA diversity was observed with genetic diversity and power of discrimination, 0.9982 and 0.9883, respectively. In this dataset the west Eurasian haplogroups predominated over the African haplogroups. The results would be useful for forensic examinations and human genetic studies.