Even Grapes Need It

Lack of Sex Among Grapes Tangles a Family Vine

For the last 8,000 years, the wine grape has had very little sex. This unnatural abstinence threatens to sap the grape’s genetic health and the future pleasure of millions of oenophiles.

The lack of sex has been discovered by Sean Myles, a geneticist at Cornell University. He developed a gene chip that tests for the genetic variation commonly found in grapes. He then scanned the genomes of the thousand or so grape varieties in the Department of Agriculture’s extensive collection.

Much to his surprise he found that 75 percent of the varieties were as closely related as parent and child or brother and sister. “Previously people thought there were several different families of grape,” Dr. Myles said. “Now we’ve found that all those families are interconnected and in essence there’s just one large family.”

 Hmmm, grapes don't seem that different to me.  Wine snobs maybe but not me.

The reason is obvious in retrospect. Vines can be propagated by breaking off a shoot and sticking it in the ground, or onto existing rootstock. The method gives uniform crops, and most growers have evidently used it for thousands of years.

Yep, that was obvious.

The purpose of sex, though this is perhaps not widely appreciated, is recombination, the creation of novel genomes by taking some components from the father’s and some from the mother’s DNA. The new combinations of genes provide variation for evolution to work on, and in particular they let slow-growing things like plants and animals keep one step ahead of the microbes that prey on them.

 Well, that may be the purpose of sex as far as grapes are concerned.