Jack w szostak biography

Every cell contains the same ‘toolbox’ of life – proteins, etc – and the body’s unique blueprint – DNA. But, as organisms grow, how does the DNA survive the process of cell division and replication without being damaged or degraded?

As early as the s, scientists had observed that whole chromosomes would not fuse together but fragments would.

They hypothesized that protective ‘caps’ called telomeres at each end prevented the inappropriate joining of chromosome ends.

Half a century later, Jack Szostak and Elizabeth Blackburn showed that a repeated DNA sequence in the telomeres protects the chromosomes ends from degradation.

Blackburn and Carol Greider then identified telomerase, the enzyme that makes telomere DNA.

When studying a single-celled organism, Tetrahymena, Blackburn noticed the DNA sequence CCCCAA was repeated several times at the ends of the chromosomes.

Meanwhile, Jack Szostak had observed that a linear DNA molecule, a type of minichro