Influence of immunologic status on age prediction using signal joint T cell receptor excision circles.

Age estimation based on quantifying signal joint T cell receptor excision circle (sjTREC) in T cells has been established to be a promising approach in forensic practice and demonstrated in different ethnic groups. Considering that the homeostasis of T cells carrying sjTRECs is closely related to the immunologic status of a person, it is important to investigate the influence of various immunologic statuses on the age estimation model. In this study, quantification of sjTREC contents was performed for groups of people with various immune system statuses, and the result showed less correlation with chronological age (r  = 0.424) than in the healthy group (r  = 0.648). The simulation model indicated that this influence could increase the range of prediction in the age estimation model, and the mean absolute deviation (MAD) between chronological age and predicted age. Through this study, it was demonstrated that immunologic status is a factor that affects the accuracy of age prediction using sjTREC quantification.