Conception to birth: TV gives us the inside story

Lewis Smith
Environment Reporter

The 20-month-old elephant foetus looks perfectly formed but still has two months before it is born

Using ultrasound, a battery of cameras and computer graphics, imaging experts have created unprecedented television pictures of animals still in the womb. Foetal dolphins are, apparently, easy to get on camera, but for elephants the procedure is rather more convoluted and involves shoulder-length rubber gloves. The pictures of live animal foetuses were created for broadcast at Christmas on Channel 4 and the National Oceanographic Channel in America.
They were recorded from the point of fertilisation through to birth, and the elephant can be seen growing from a singie cell to a 2601b (118kg) newborn. One of the world's leading ultrasound experts, Thomas Hilderbrandt, was brought in by the producers to record 4-D images from inside the wombs of dogs, dolphins and elephants.
The dogs would lie down for the procedure; the dolphins were trained to swim against the ultrasound equipment; but the elephants had to be given an enema before a probe was pushed up the rectum to get close enough to the foetus to generate images.
Jeremy Dear, of Pioneer Productions, which made the 90-minute programme, said that the star sequence was a computer-generated scene of the elephant foetus moving down the birth canal, before switching to a live exterior shot of an elephant birth.
"It gets an 'ahhh' every time," he said "It's anthropomorphism gone mad, but it's very effective" He added: "The key to this is that it opens up this unseen world of the animal womb. The reason we got such co-operation from zoos and vets in making the film is that they were really keen to see what actually goes on in the womb. What we've done is make it visual."
Several animals of each species were used to create the images, but the pictures were mixed together to provide viewers with a sequential story following the creatures from conception to birth. The golden retriever can be seen panting in the womb with its tongue hanging out, and the dolphin foetus can be seen at eight weeks, the point at which it starts to learn to swim. It has another ten months before birth. During the programme, At eight weeeks,the dolphin starts to learn how to swimevolutionary stages from millions of years ago can be seen. Leg-like buds appear on the dolphin, then vanish. Similarly, the elephant develops ducts normally found in freshwater fish. Mr Dear said: "The film underlines some fascinating facts about our evolutionary heritage and you can't help be moved by each of our animal's journeys towards birth. "Via a combination. of advanced technology, in-depth timeline of each foetus's development and birth, and state-of-the-art computer-generated graphics, Animals in the Womb offers a pretty extraordinary window on this previously unseen world" [Note that the programme also said that elephant's testes are held inside their body showing a heritage from the sea - hardly a creature CREATED for the land!-LB]
TIMES Thursday November 23,2006 3WC


Genetic jot that makes us unique

Mark Henderson

Science Editor

  • Humans are less alike than thought

  • Chimps are not such close relatives

The genetic differences between individual human beings are much greater than was previously thought, according to research that offers a fresh explanation for the unique physical and psychological characteristics of every person.
A revolutionary map that compared the genomes of 270 people has shown that humans are not 99.9 per cent genetically identical as assumed, but that much more of our DNA varies between one person and the next.
Whereas previous analysis of the human genome had suggested that no more than 0.1 per cent of it underlaid all the genetic differences between individuals, the new findings indicate that at least three times more DNA actually varies.
The results reveal a new category of genetic diversity that promises to explain certain inherited disorders, and why some people are more susceptible to diseases or respond badly to particular drugs. The work could be especially significant for HW/Aids, Parkinson's disease, Alzheimer's disease and developmental disorders similar to Down's syndrome, which can all be affected by the newly identified disparities.
The extra variation also expands the ways in which a person's DNA profile can affect temperament and behaviour, and points to previously unknown genetic differences between Homo sapiens and our closest animal relative, the chimpanzee.
Just as humans seem to be 0.3 per cent genetically different from one another, and not 0.1 per cent, so we may be 3 per cent and not 1 per cent different from chimps, scientists behind the study say. Charles Lee, of Harvard Medical School, a leader of the research, said: "The evidence shows that we are more genetically unique,compared to one another.
That is gratifying in a way. We are all physically different, and we all react differently to environmental stimuli - and to drugs.
"We are also finding evidence that could help to explain why humans are not chimps. We can safely say that there's a lot more genetic variation between the human genome and the chimp genome than was appreciated."
The first studies of the human genome, which was mapped five years ago, reached the figure of 0.1 per cent variation between individuals by looking at changes in single DNA "letters" known as single nucleotide polymorphisms, or SNPs.
Similar studies put the genetic difference between humans and chimps at about 1 per cent of DNA This surprisingly low genetic variation led many sdentists to wonder how so little DNA could be responsible for such significant differences as those between individual humans, and between humans and other animals.
The new research offers an answer: the old estimates were incomplete. It has expanded the range of variation by looking also at much larger segments of genetic code, which can be repeated many times or deleted entirely from the genome. While most people have two copies of each gene, one inherited from each parent, some genes or fragments of genes can be absent altogether, or repeated five or ten times over in certain individuals.
These changes, known as copy number variation (CNV), sometimes have no obvious effects, but they can influence disease or other aspects of human development An international research 20-25,000 Number of genes thought to be in human genome (earlier estimate 100,000) Source:Human Genome Projectteam has now mapped the genome for CNV, encompassing genetic changes of 500 or more DNA letters. Their results, published today in the journal Nature, show that '2 per cent of the human genome is susceptible to such variation.
Not all these possible changes will separate any two individuals, but scientists think that their genomes will usually vary by about 0.3 per cent .
Matthew Huries, of the Wellcome Trust Sanger Institute, in Hinxton, Cambridgeshire, a leader of the research, said: "The variation that researchers had seen before was simply the tip of the iceberg, while the bulk lay submerged, undetected.

Fuji the Dolphin

http://www.world-science.net/othernews/061123_variation.htm


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