It's been one week since the Bahamas-based company Clonaid announced the birth of the alleged world's first human clone, a baby named Eve. The claim immediately met with widespread skepticism among scientists for several reasons: reproductive cloning has yet to be achieved in primates, the birth was announced at a press conference rather than in a peer-reviewed publication, and the company has yet to provide so much as photographic evidence of a baby.

Not strengthening its case, Clonaid is affiliated with the Raëlian sect, whose founding tenet is that humans were cloned from extraterrestrials. In light of past fraudulent claims to have cloned humans, this latest – if it's to be taken seriously – will have to be verified independently and thoroughly.

In an attempt to do just that, Clonaid has agreed to allow freelance science reporter Michael Guillen to orchestrate independent genetic testing of the baby. A science correspondent for ABC News for 14 years, Guillen has a doctorate in physics, mathematics, and astronomy from Cornell University. At a press conference held December 27 with Clonaid's CEO, Brigitte Boisselier, Guillen outlined a proposed testing schedule. Blood samples were to be taken from mother and child this week, tested at two labs to verify a genetic match, and the results would be available sometime next week.

Guillen has not identified the labs performing the testing, nor precisely what kinds of tests will be performed. Since last week's press conference he has refused further public comment, and his agent's office told The Scientist that Guillen will continue a "no comment" policy until the test results become available.

Until that time, scientists can only speculate about the truth of the claim that the baby is a clone of her birth mother. While not probable at this stage, successful human reproductive cloning is certainly possible. "Many physicians have the skills to collect human ova and transfer human embryos, and many technicians could perform the nuclear transfer procedure," said Mark Westhusin associate professor with the College of Veterinary Medicine of Texas A&M University, College Station.

According to Westhusin, who heads a lab that last year produced the world's first cloned cat, analysis of DNA short tandem repeats (STRs) from the mother and baby's nuclear DNA could prove whether the child is indeed a clone. STRs are highly polymorphic among individuals, and if enough markers are analyzed, compared and found to be identical, then statistics can predict the probability of the mother and child being genetically identical, Westhusin told The Scientist.

Bruce Weir, professor of statistics and genetics at North Carolina State University and a DNA forensics expert who testified in OJ Simpson's trial, concurs that a standard 13-locus microsatellite (STR) forensic profile should be identical for the mother and child. He also pointed out that the mitochondrial DNA of the baby should be identical to that of the donor from which the oocyte was derived.

Perhaps the biggest issue in establishing the truth of the claim will be verifying the chain of custody of the samples. Tests must be conducted in duplicate by separate laboratories, noted Sir Alec Jeffreys, the inventor of DNA fingerprinting and professor of genetics at Leicester University, UK, in a written statement issued by the Royal Society on December 31.

According to Jeffreys, independent experts would also have to witness every step of the procedure for collecting the tissue samples of mother and baby so that they could vouch for the authenticity of the samples.

Beyond establishing the baby's identity, further testing would be needed to determine its health. Rudolf Jaenisch professor of biology at the Whitehead Institute claims that even if DNA evidence verifies that the infant is a clone, it's unlikely to be healthy or stay healthy. Animal experiments predict that the baby would have "all kinds of problems," he told The Scientist. The few clones that survive birth tend to have abnormal fetal development called large offspring syndrome. "So the ones that survive the perinatal period appear normal afterwards, but they are not."

Jaenisch and colleagues have studied gene expression in cloned mice, and have found hundreds of genes to be incorrectly expressed. "There's no reason to assume that what we see in mice would be different for humans," he said.

He also pointed out that brain function is a concern, and "of course, none of these brain effects have been tested in animals, because they are not suitable for that," he said. "One would predict that any clone that ages would have more and more of these problems."

Jaenisch, like many, is skeptical. "If these people supply any results, I wouldn't believe them," he said. "You need credible people doing this, not some charlatans."