Driven by her fascination with highly repetitive, hard-to-read parts of our DNA, Karen Miga led a coalition of researchers to finish sequencing the human genome after almost two decades.
By 2001 the Human Genome Project (HGP) had prepared a rough draft, and in April 2003, the draft sequence was declared finished. But Karen Miga, a geneticist now at the University of California, Santa Cruz and the associate director of the UCSC Genomics Institute, knew that while the work might have wrapped up, the sequencing was far from complete.
The HGP was able to sequence the 90% of human DNA that geneticists call euchromatin, which is loosely folded and contains nearly all of the genes that are actively making proteins. But Miga specialized in heterochromatin, the tightly packed sections of DNA with highly repetitive sequences near the ends (telomeres) and centers (centromeres) of chromosomes. At the time, scientists couldn’t sequence heterochromatin, so despite the celebratory hubbub and champagne toasts, almost 10% of the genome went unsequenced.
Together with Adam Phillippy, a computational biologist at the National Human Genome Research Institute, Miga launched the Telomere-to-Telomere (T2T) consortium in 2018 to finally sequence every last nucleotide of human DNA.