Abstract:
Analysis of Short Tandem Repeat (STR) markers on the human genome is an important
tool in the identification of individuals based on their genetic makeup. DNA extracted
from materials of biological evidence is subjected to Polymerase Chain Reaction (PCR) to
generate DNA profiles, unique to an individual. However, forensic analysts are
challenged to obtain a complete DNA profile by the failure in PCR amplification of such
biological evidence due to several factors: for example, high humidity and temperature in
the tropics (as in Sri Lanka), promote the degradation of such biological materials and
rapidly reduce the possibility of typing such nuclear DNA. Conventional PCR technology
used in Sri Lanka analyses amplicons generated in the size range of 150 to 450 nucleotide
bases. Hence, DNA in a biological sample fragmented into smaller sizes cannot be
amplified by PCR. Therefore, we have evaluated the application of three new miniaturized
–Short Tandem Repeat markers (mini-STRs) screened for possible application in degraded
DNA evidence analysis. These novel STR markers are capable of generating smaller sized
PCR amplicons (less than 150 bp) by PCR. No previous studies have been recorded in the
application of these three STR loci.
