Kinship analysis and allelic dropout: a forensic approach on an archaeological case

Abstract

Background: This study relies on the discovery of two pit burials (LTA and LTB) of the Bronze Age Cogotas I archaeological culture (circa 3600–2950 BP) in Spain. LTA was a single burial and LTB contained three skeletal remains of two adults and a newborn or foetus at term.

Aim: The central question posed by this find was whether the LTB tomb constituted a traditional nuclear family (father, mother and son or daughter).

Methods: Ancient and forensic DNA protocols were employed to obtain reliable results. Autosomal, X-STR markers and mitochondrial DNA were amplified. Subsequently, different kinship probabilities were estimated by means of LR values calculated using the Familias 3 software. Furthermore, an allelic dropout sensitivity test was developed in order to evaluate the influence of allelic dropout phenomena on the results.

Results: It was possible to determine the molecular sex of all individuals and to establish a maternal relationship between the perinatal individual and one of the adults.

Conclusion: The remains in the LTB tomb were not a traditional nuclear family (father, mother and son/daughter) and it was probably a tomb where two women, one of them pregnant, were buried.

Keywords:

• Ancient DNA
• low template DNA
• multiple burial
• biological relationships
• Iberian Bronze Age

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

This work has been possible by the projects HAR2009–10105 and HAR2013–43851-P funded MINECO (Spanish Government) and BES2010–035322FPI grant.