DNA analysis not foolproof

The report on the Criminal Investigation Department's (CID) forensics division seems to give the impression that with DNA analysis, the CID now has the panacea for solving crimes (From 12-man team to 100-strong forensics unit; Nov 10).

The DNA molecular structure was first identified in 1953 and it was only 38 years later that Singapore's CID began using DNA analysis in forensic cases.

DNA evidence can be unequivocal under ideal conditions - for instance, when officials have a large quantity of a suspect's well-preserved genes.

However, there can be mistakes made during laboratory sequencing in some cases.

The mishandling, mislabelling or contamination of DNA samples, such as a suspect's blood, semen and saliva, may also compromise the analysis.

Depending heavily on DNA analysis could give rise to wrong convictions.

Heng Cho Choon

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A version of this article appeared in the print edition of The Straits Times on November 13, 2017, with the headline DNA analysis not foolproof. Subscribe