In recent years, Low Copy Number biological evidence plays an increasingly important position in forensic DNA analysis.

近年来，低拷贝模板类生物物证受到广泛关注并在法医dna分析中占有了越来越重要的地位。

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The DNA had been discovered using a new technique called "low copy number DNA".

BBC: Omagh: 10 years on

The cases would specifically involve Low Copy Number (LCN) DNA samples which involve tiny traces of DNA that have only been detectable with new techniques available since 2001.

BBC: DNA sample being taken