Pigs Join the Clone Menagerie

<%=company1%> announced that it has cloned some pigs—five in all---and their names are Millie, Christa, Alexis, Carrel and Dotcom, for various reasons, some obvious, some not*. According to a Reuters report, cats will be next.

Pig cloning, however, represents both a technical achievement and potentially an important pathway to tissues and organs for use in transplantation studies. Technically, pigs have been difficult to clone because the sow apparently needs to have a litter of a certain size in order for the pregnancy to be successful. PPL had to invent a different procedure from the one used for Dolly and her successors, for which it filed a patent application.

And on the clinical front, cloned pig tissues may someday provide material for human transplantation. The PPL researchers are already working on the next step, which is to engineer the pig cells not to make transplantation antigens that cause rejection in humans.

In what might be a bit of an overstatement, Dr. Ron James, PPL's managing director was quoted as saying "An end to the chronic organ shortage is now in sight. The next step for PPL is to repeat the pig cloning experiment to produce knock-out pigs."

The "knock-out" pigs James referred to have the gene for a 1,3 gal transferase, thought to trigger hyperacute organ refection in humans, turned off. PPL has already produced knock-out cells, and it hopes to have a knock-out pig within a year. Company scientists are also working on controlling three other causes for long term organ rejection.

The company expects clinical trials in humans could get underway in four years, but the xenograft program needs additional funds to the tune of $20 million funds to get to that stage.

And as for you cat lovers, Japanese scientists at Yamaguchi University, in eastern Japan, are poised to implant an egg bearing the genetic material of a dead cat fetus into a surrogate mother cat, the Kyodo News Agency reported.

``I am hoping to use this technique to preserve Iriomote wildcats, Siberian Tigers and other felines in danger of extinction,'' Tatsuyuki Suzuki, a professor at the university was quoted as saying.

* Millie was named for the millennium. Christa after Dr. Christian Barnard, who performed the first human heart transplant, Alexis and Carrel after Dr. Alexis Carrel, who won the Nobel Prize in 1912 for his work in the field of transplantation, and Dotcom, well "Any association with dot-coms right now seems to have a very positive influence on a company's valuation," said James.

By Laura DeFrancesco