1. ¹Section of Hemato-Oncology, Department of Medicine, Taipei Veterans General Hospital, and School of Medicine, National Yang-Ming University, Taipei, Taiwan
2. ²Section of Transfusion Medicine, Department of Medicine, Taipei Veterans General Hospital, and School of Medicine, National Yang-Ming University, Taipei, Taiwan

Correspondence: Dr C-H Tzeng, Section of Transfusion Medicine and Section of Hemato-Oncology, Department of Medicine, Taipei Veterans General Hospital, and School of Medicine, National Yang-Ming University, 201 Shih-Pai Road, Section 2, Taipei 11217, Taiwan. E-mail: chtzeng@vghtpe.gov.tw

³These authors contributed equally to this work.

Received 25 May 2007; Revised 26 June 2007; Accepted 5 July 2007; Published online 20 August 2007.

Abstract

Blood, buccal swab and hair follicles are among the most commonly used sources for forensic science, parentage testing and personal identification. A total of 29 patients who have had a sustained engraftment from 15 months to 21.5 years after allogeneic hematopoietic stem cell transplantation (HSCT) without rejection, relapse or chronic GVHD involving oral mucosa were enrolled for a chimerism study. PCR-amplified short tandem repeat analyses were conducted per patient every 3 months for at least three consecutive times. The results for blood were all donor type except one who had a mixed chimerism, 14.5 years after receiving a transplant for lymphoma. As for buccal swab, mixed chimerism ranging from 10 to 96% donor origin was noted for 28 recipients except the one who had mixed chimerism of blood and retained total recipient type. In contrast, hair follicles were 100% recipient type for the entire group. It is concluded that the hair follicle is devoid of adult stem cell plasticity and may serve as a reliable source of recipient's origin when pre-transplant DNA fingerprinting or reference DNA is not available for people who have successfully received allogeneic HSCT while in need of a personal identification.