[4] Clark's research has advanced understanding of the role of DNA methylation, non-coding RNA and microRNA in embryogenesis, reprogramming, stem cell development and cancer, and has led to the identification of epigenomic biomarkers in cancer.
[5][6] Clark is a founding member of the International Human Epigenome Consortium (IHEC) and President of the Australian Epigenetics Alliance (AEpiA).
She earned a PhD (1982) in Biochemistry at the University of Adelaide, by mapping and sequencing human histone genes, under the supervision of Dr Julian Wells.
As Group Leader of the Gene Regulation Unit at the Kanematsu Laboratories, Royal Prince Alfred Hospital from 1992 - 2000, Clark developed highly sensitive techniques that enabled DNA methylation sequencing of single genes from small volumes (<100 cells) using sodium bisulphite, which converts cytosine residues to uracil residues in single-stranded DNA, under conditions that preserve 5-Methylcytosine.
In 2000, Clark established the Epigenetics Group at the Sydney Cancer Centre, Royal Prince Alfred Hospital and led the unit until 2004.