castanyes blaves

Amemiya and his co-workers became suspicious that the lamprey's genome structure and composition was changing during development when they heard rumors lamprey genome sequences efforts were being complicated by genome fragmentation. They speculated that this might be due to genome rearrangements similar to those described for the hagfish, a chordate and superficially similar organism.

To test this, the researchers compared germ line and somatic tissues from sea lamprey caught in Lake Michigan.

Indeed, they found that the genome was larger in sperm (germ line cells) than in adult blood nuclei (somatic cells), even within the same individual. The sperm cells also contained more DNA than kidney and liver cells, which both had similar DNA content to red blood cells. Overall, the researchers noted, sperm genomes contained some 20 percent more DNA than adult cells such as red blood cells.