Malignant tumors and forensics--dilemmas and proposals.
OBJECTIVE
To evaluate the effect of genetic instability and degradation in archived histology samples from cancerous tumors and to investigate the validity of short tandem repeat (STR) typing of these samples and its potential effect on human identification.


METHODS
Two hundred and twenty eight slides of archival pathology tissues from 13 different types of malignant tumors were compared with healthy tissues from the same individuals. DNA analysis was performed using standard techniques for forensic STR analysis, PowerPlex16 and Identifiler on 2 distinct sample sets. Genetic instability was assessed by comparing reference tissues with cancerous tissues derived from the same individual. Loss of heterozygosity, a > or =50% reduction in heterozygosity ratio between healthy and diseased samples, and microsatellite instability, the presence of an additional allele not present in reference tissue, were assessed. The quality of profiles obtained with respect to completeness among the archived samples and degradation using the 2 platforms were also compared.


RESULTS
Profiles obtained using the Identifiler system were generally more complete, but showed 3-fold higher levels of instability (86%) than those obtained using PowerPlex 16 (27%). Instances of genetic instability were distributed throughout all loci in both multiplex STR systems.


CONCLUSIONS
After having compared 2 widely used forensic chemistries, we suggest individual validation of each kit for use with samples likely to exhibit instability combined with fixation induced degradation or artifact. A "one size fits all" approach for interpretation of these samples among commercially available multiplexes is not recommended.
Budimlija
Zoran
Z
Department of Forensic Biology, New York City Office of Chief Medical Examiner, 421 East 26th Street, New York, NY 10016, USA. zbudimlija@ocme.nyc.gov
Lu
Connie
C
Axler-DiPerte
Grace
G
Seifarth
Jessica
J
Popiolek
Dorota
D
Fogt
Franz
F
Prinz
Mechthild
M
D049429:Forensic Pathology; D042822:Genomic Instability; D006801:Humans; D019656:Loss of Heterozygosity; D018895:Microsatellite Repeats; D009369:Neoplasms / Q000235:genetics* / Q000473:pathology