Genes Now Tell Doctors Secrets They Can’t Utter August 25, 2012 Dr. Arul Chinnaiyan stared at a printout of gene sequences from a man with cancer, a subject in one of his studies. There, along with the man’s cancer genes, was something unexpected — genes of the virus that causes AIDS. It could have been a sign that the man was infected with H.I.V.; the only way to tell was further testing. But Dr. Chinnaiyan, who leads the Center for Translational Pathology at the University of Michigan, was not able to suggest that to the patient, who had donated his cells on the condition that he remain anonymous. In laboratories around the world, genetic researchers using tools that are ever more sophisticated to peer into the DNA of cells are increasingly finding things they were not looking for, including information that could make a big difference to an anonymous donor. [...] http://www.nytimes.com/2012/08/26/health/research/with-rise-of-gene-sequencing-ethical-puzzles.html [ http://www.nytimes.com/2012/08/26/health/research/with-rise-of-gene-sequencing-ethical-puzzles.html?pagewanted=all ]
Chandra Bahadur Dangi, World's Shortest Man, Meets Jhoti Amge, World's Shortest Woman (VIDEO) To promote the newest edition of Guinness World Records, Chandra Bahadur Dangi, who at 21.5 inches is the world's shortest man, met the world's Shortest Woman, Jyoti Amge, who measures 24.7 inches. Jyoti Amge, 18, of Nagpur, India, who is 24.7 inches tall, has just been declared the world's smallest living woman. Amge is a budding fashionista who customizes her own clothes and jewelry. She is also pursuing a career as an actress in Bollywood films. 08/29/2012 http://www.huffingtonpost.com/2012/08/29/worlds-shortest-man-woman-meet-chandra-bahadur-dangi-jhoti-amge_n_1838381.html [with embedded video, and comments]
Virgin births discovered in wild snakes 12 September 2012 Last updated at 00:45
By Jeremy Coles Reporter, BBC Nature
Charles Smith and Pam Eskridge - A virgin female and her son
A form of virgin birth has been found in wild vertebrates for the first time.
Researchers in the US caught pregnant females from two snake species and genetically analysed the litters.
That proved the North American pit vipers reproduced without a male, a phenomenon called facultative parthenogenesis that has previously been found only in captive species.
Scientists say the findings could change our understanding of animal reproduction and vertebrate evolution.
He and his collaborators investigated virgin births in wild populations of two geographically separated and long-studied species of snake.
“The frequency is what really shocked us” Dr Warren Booth University of Tulsa
They captured pregnant copperhead and cottonmouth female pit-vipers from the field, where males were present.
The snakes gave birth, allowing the scientists to study the physical and genetic characteristics of the litters.
Of the 22 copperheads, the scientists found one female that must have had a virgin birth.
Another single virgin birth occurred within the 37 cottonmouth litters.
"I think the frequency is what really shocked us," said Prof Booth.
"That's between 2.5 and 5% of litters produced in these populations may be resulting from parthenogenesis.
"That's quite remarkable for something that has been considered an evolutionary novelty," he said.
Sex or no sex
A virgin birth, or parthenogenesis, is when an egg grows and develops without being fertilised by sperm.
It results in offspring that only have their mother's genetic material; no fatherly contribution is required.
This is not uncommon in invertebrates such as aphids, bees and ants.
It also happens in a few all-female species of lizard; geckos and whiptails for example. But here it occurs across a generation; all female reproduce asexually via a process called obligate parthenogenesis.
But asexual reproduction by a normally sexual vertebrate species is still rare, having been reported in under 0.1% of species.
It was only in the mid-1990s that virgin births began to be documented in captive snakes, followed by a captive giant lizard in 2006 and a captive shark in 2007.
Rolf Nussbaumer - All female species, such as some whiptail lizards, reproduce asexually
To date this now includes around 10 species of snakes including a couple of boas, and a python, four species of shark, and several monitor lizards, including the endangered Komodo dragon.
Recently the zebra finch and Chinese painted quail were added to the list. All were kept in isolation in unnatural conditions and away from any males.
So to find asexual reproduction in two species of snake in the wild on their first attempt was "astounding", according to Prof Booth and his collaborators.
Virgin births should no longer be viewed as "some rare curiosity outside the mainstream of evolution," he said.
Evolutionary dead-end?
It remains unclear whether the female snakes actively select to reproduce this way, or whether the virgin births are triggered by some other factor, such as a virus or bacterial infection.
"Any answer is pure speculation at this point," says Prof Booth.
In captivity, two sharks, and three snakes, have been shown to have had multiple virgin births, producing more than one litter via facultative parthenogenesis.
As yet, it also remains unclear whether the offspring of these wild virgin births can themselves go on to have normal, or virgin births of their own.
In captive snakes studied so far, offspring have so far not been proved viable, that is capable of surviving and reproducing.
Tom Spink / Flickr Cottonmouth pit vipers are capable of virgin births in the wild
However, earlier this year Prof Booth and colleagues reported that a checkered gartersnake that has had consecutive virgin births, appears to have produced viable male offspring.
Parthenogenicly born copperheads and cottonmouths are also currently being raised and "in the next two to three years we will know if they are indeed viable," said Prof Booth.
"If they cannot survive and reproduce, then this is a reproductive dead-end.
"However, if they are healthy and can reproduce, that opens an entirely new avenue for research," he said.
Being able to switch from sexual to asexual reproduction could be advantageous; in the absence of males a female could still give birth and start a new, albeit inbred, population.
Her genes could still be passed on via her fertile male offspring.
Scientists believe that facultative parthenogenesis is more common in some lineages such as reptiles and sharks.
However it is unlikely that similar virgin births will be found among placental mammals, which include all the mammals aside from the platypus and echidnas.
That is because mammals require a process called genomic imprinting to reproduce, where a set of genes from one parent dominates over the other. The interaction between the two sets of parental genes is required for embryos to develop normally.