Sir, – As someone who has witnessed first-hand spectacular technical advances in the fields of ancient DNA and genomics during the last two decades, I am perplexed by the hesitancy in applying modern forensic genomics to genetic identification of the skeletal material found at the Tuam mother and baby home ("Katherine Zappone warns over DNA testing of Tuam remains", News, December 29th).
First demonstrated by researchers at UCD and TCD, it is now well established that the best source of human DNA from archaeological material is the dense petrous portion of the temporal bone located in the skull. This relatively small skeletal element can be easily accessed and genetic profiling using high-throughput DNA sequencing would not be compromised by co-mingling of skeletal material or cross-contamination of DNA from different individuals. In addition, at less than a century, the age of these skeletons is unlikely to be a problem for these methods; scientists routinely generate whole-genome sequence information from people that lived thousands of years ago.
Integration of high-throughput DNA sequencing data with single-nucleotide polymorphism (SNP) “chip” data from putative living relatives would provide thousands-if not tens of thousands-of genomic markers that could be used for highly accurate and rapid genetic matching to the children interred at the Tuam site. – Yours, etc,
DAVID MacHUGH, PhD
Professor in Genomics,
University College Dublin,
Belfield, Dublin 4.