Nucleic Isolation

NUCLEIC ISOLATION BY THE USE OF A NON-IONIC DETERGENT AS AN AID TO EXTRACTING DNA FROM TISSUE SAMPLES.

L.J. Mendoza, R. M. Thompson, T.H. Aulinskas, and H.C. Coleman,
GeneLex Corporation, 2203 Airport Way S,
Seattle, WA 98134

DNA analysis allows for forensic and parentage testing of tissues that may have been subjected to interment or archival preparation. DNA analysis of tissues can now demonstrate genetic relationships in body identification, child abandonment and routine paternity. Prenatal and perinatal tissue specimens can be used in rape and incest cases. A preparative method has been adopted that selectively isolates the nuclei from cellular and stromatic materials. The purpose of this method is to concentrate intact DNA prior to nuclei lysis and digestion. This is achieved by the use of the non-ionic detergent Nonidet-P40 which lyses the cytoplasmic membrane while leaving the nuclear membrane intact. Following this procedure the DNA may be further purified using organic or non-organic methods. This method selectively isolates DNA of higher molecular weight from decomposed tissue samples. Autoradiograms of DNA purified by this method show decreased lane background as typically seen with partially degraded DNA specimens. Our laboratory routinely uses Nonidet-P40 followed by non-organic extraction for all tissue samples including decomposed and autopsy, abortus and placental tissue. FBI92-1