Joseph Grafton Gall (April 14, 1928 – September 12, 2024) was an American cell biologist whose studies revealed many details of chromosome structure and function.
[1] He was also a co-recipient (with Elizabeth Blackburn and Carol W. Greider) of the 2007 Louisa Gross Horwitz Prize from Columbia University.
Later, staining with DAPI, a more sensitive dye, revealed the DNA running through each loop and then returning to the axis of the chromosome.
[8] When Elizabeth Blackburn, 2009 Nobel laureate in Medicine, worked with Gall they analyzed the ends of chromosomes and identified the major short repeated sequence that occurs in telomeres of most higher organisms.
Blackburn and her student Carol Greider later discovered the enzyme telomerase that maintains the lengths of the protective telomeric sequences and identified its role in aging.
But she urged a young Joseph Gall to explore the natural world, encouraging him to catch bugs and bring them into the house so together they could identify the creatures using scientific reference books.