He and his research group discovered the cause of chronic myelogenous leukemia and furthered the understanding of the nucleotide excision repair.
[4] After completing his PhD, Bootsma joined the newly founded Department of Cell Biology and Genetics at Erasmus University Rotterdam.
[1] Later, Bootsma shifted his focus from gene mapping to cancer research, building on his earlier experiences at TNO.
He invested mechanisms of DNA repair, particularly in rare forms of skin cancer, and discovered several proteins in this field.
[4] Bootsma had a special interest in chromosome 22, which was recently implicated in chronic myelogenous leukemia.
[12] In 2009, Bootsma's discovery of the relation between chronic myelogenous leukemia and the Philadelphia chromosome was incorporated in the Dutch canon of medicine.