RESUMO
ObjectiveTo examine whether DNA extracted from free edge fingernails specimens from patient after hematopoietic stem cell transplantation (allo-HSCT) could be used for short tandem repeat (STR) genotyping and chimerism analyzing,and to observe the chimerism status in fingernails after allo-HSCT.MethodsPeripheral blood,bone marrow,oral mucosa and free edge fingernail specimens were collected from 25 patients which allo-HSCT were performed in Beijing Dao-pei Hospital during Jul.2009 to Sep.2011 and their donor.Genomic DNA was extracted and 15 STR loci genotyping and chimerism analysis were performed.For the first group which including 12 patients,pairs of fingernail and oral mucosa specimens were collected within one month after allo-HSCT and were comparative analyzed.For the second group which including 13 patients,chimerism status in fingernail samples were analyzed 3 months or longer after allo-HSCT,and 3 patients underwent repeated testing at different times.ResultsFor the first group,4 oral mucosa specimens showed donor chimerism with varying degrees,but no donor chimerism was detected.in all of 12 fingernail specimens.For the second group,6.7％ to 82.6％ donor chimerism was detected in fingernail specimens in 5 out of 13 patients.For the 3 patients underwent repeated testing,donor chimerism was continued negative in one cases,but continued positive in the other 2 cases.ConclusionsFree edge fingernail samples of patients within one month after allo-HSCT can be used for STR typing and chimerism analysis,and it is better than oral mucosa samples.There are cells in allo-HSCT donor graft can differentiate into skin cells,donor derived skin cells chimerism can be formed and persist in some patients.Med,2012,35:23-26)