Show Details

Dad’s Diversity

July 31, 2012

Sequencing the DNA of individual sperm helps explain why siblings are often so different.

Transcript

BOB HIRSHON (host):

The father of variety…I’m Bob Hirshon and this is Science Update.

About half of your DNA comes from your father and half from your mother. But each sperm and egg has its own unique mix of genes, which helps explain the differences between siblings. Now, Stanford scientists have decoded the entire genome of 91 individual sperm from a single man. Biophysicist Stephen Quake says the project has revealed much more diversity in a male’s sperm than previously thought. For instance, his team found many places where genes mix in non-random ways as a sperm is being formed. In addition, the rate of new mutations between a man and his sperm was much higher than previous estimates.

STEPHEN QUAKE (Stanford University):

That’s another source of variation in your potential children. We measured typically 10 new mutations per sperm cell.

HIRSHON:

Quake says the findings shed light on the variety of human traits.

QUAKE:

And it helps us understand how genomes from unrelated people get woven together to create new members of the human race.

HIRSHON:

I’m Bob Hirshon, for AAAS, the science society.

Siblings often bear a strong resemblance to each other, but they can also be surprisingly different. (Wikimedia Commons/Sarah W.)