Dr. Pille Hallast is a Research Scientist at The Jackson Laboratory for Genomic Medicine (USA), where she studies genome diversity and the structure and evolution of the Y chromosome, with a particular interest in how genetic variation in complex genomic regions influences genome function, human health, and reproduction. She completed her undergraduate, master’s, and doctoral training at the University of Tartu, where her early work focused on segmentally duplicated gene clusters involved in human reproduction and their evolution in primates.

Her subsequent research has centred on the Y chromosome as both a marker of human demographic history and a model for studying mutational processes in structurally complex regions of the genome. As a postdoctoral researcher at the University of Leicester and later at the University of Tartu and the Wellcome Sanger Institute, she contributed to some of the first population-scale resequencing studies of the Y chromosome, revealing high rates of gene conversion, new patterns of global diversity, and links between Y-chromosomal variation and human disease and male infertility.

More recently, she has applied long-read sequencing and de novo assembly approaches to resolve previously inaccessible regions of the genome. She is a co-author of the first complete human Y chromosome assemblies, published in Nature in 2023, and is actively involved in the Human Structural Variation Consortium, which aims to improve the detection and characterisation of structural variants and complex genomic regions in diverse human populations.

Why the Y? Long-read assemblies and new insights into diversity and mutation in complex genomic regions