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Baby’s rare brain tumor had teeth

Baby’s rare brain tumor had teeth

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Published February 27, 2014

A 4-month-old infant in Maryland may be the first person to have had teeth form in his brain as a result of a specific type of rare brain tumor, according to a new report of the case.

The boy is doing well now that his tumor has been removed, and doctors say the case sheds light on how these rare tumors develop.

Doctors first suspected something might be wrong when the child’s head appeared to be growing faster than is typical for children his age. A brain scan revealed a tumor containing structures that looked very similar to teeth normally found in the lower jaw.

The child underwent brain surgery to have the tumor removed, during which doctors found that the tumor contained several fully formed teeth, according to the report. [14 Oddest Medical Cases]

After an analysis of tumor tissue, doctors determined the child had a craniopharyngioma, a rare brain tumor that can grow to be larger than a golf ball, but does not spread.

Researchers had always suspected that these tumors form from the same cells involved in making teeth, but until now, doctors had never seen actual teeth in these tumors, said Dr. Narlin Beaty, a neurosurgeon at the University of Maryland Medical Center, who performed the boy’s surgery along with his colleague, Dr. Edward Ahn, of Johns Hopkins Children’s Center.

“It’s not every day you see teeth in any type of tumor in the brain. In a craniopharyngiomas, it’s unheard of,” Beaty said.

Craniopharyngiomas commonly contain calcium deposits, “but when we pulled out a full tooth…I think thats something slightly different,” Beaty told Live Science.

Teeth have been found in people’s brains before, but only in tumors known as teratomas, which are unique among tumors because they contain all three of the tissue types found in an early-stage human embryo, Beaty said. In contrast, craniopharyngiomas have only one layer of tissue.

The boy’s case provides more evidence that craniopharyngiomas do indeed develop from the cells that make teeth, Beaty said.

These tumors are most often diagnosed in children ages 5 to 14, and are rare in children younger than 2, according to the National Cancer Institute.

The boy is progressing well in his development, the researchers said. However, because craniopharyngiomas are tumors of the pituitary gland a gland in the brain that releases many important hormones they often cause hormone problems.

In the boy’s case, the tumor destroyed the normal connections in the brain that would allow certain hormones to be released, Beaty said, so he will need to receive hormone treatments for the rest of his life to replace these hormones, Beaty said.

“He’s doing extremely well, all things considered,” Beaty said. “This was a big tumor right in the center of his brain. Before the moderate surgical era this child would not have survived,” Beaty said.

The teeth were sent to a pathologist for further study, Beaty said, and generally, these types of tissue samples are saved for many years in case more investigation is needed.

The report is published in the Feb. 27 issue of the New England Journal of Medicine.

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Could humans be cloned?

Could humans be cloned?

By Rachael Rettner

Published May 19, 2013

LiveScience

  • Battlestar Galactica cylons.jpg

    Actresses Tricia Helfer (left) and Grace Park (right), who played humanoid Cylons with countless clones on the TV show “Battlestar Galactica.” (Syfy)

  • Egg nucleus transfer final.jpg

    The first step during SCNT is enucleation or removal of nuclear genetic material (chromosomal) from a human egg. An egg is positioned with holding pipette (on the left) and egg’s chromosomes are visualized under polarized microscope. A hole is made in the egg’s shell (zone pellucida) using a laser and a smaller pipette (on the right) is inserted through the opening. The chromosomes then sucked in inside the pipette and slowly removed from the egg. (Cell, Tachibana et al.)

The news that researchers have used cloning to make human embryos for the purpose of producing stem cells may have some people wondering if it would ever be possible to clone a person.
Although it would be unethical, experts say it is likely biologically possible to clone a human being. But even putting ethics aside, the sheer amount of resources needed to do it is a significant barrier.

Since the 1950s when researchers cloned a frog, scientists have cloned dozens of animal species, including mice, cats, sheep, pigs and cows.

‘It’s grossly unethical.’

– Dr. Robert Lanza, chief scientific officer at the biotech company Advanced Cell Technology 

In each case, researchers encountered problems that needed to be overcome with trial and error, said Dr. Robert Lanza, chief scientific officer at the biotech company Advanced Cell Technology, which works on cell therapies for human diseases, and has cloned animals.

With mice, researchers were able to use thousands of eggs, and conduct many experiments, to work out these problems, Lanza said. “Its a numbers game,” he said.

But with primates, eggs are a very precious resource, and it is not easy to acquire them to conduct experiments, Lanza said.

In addition, researchers can’t simply apply what they’ve learned from cloning mice or cows to cloning people.

For instance, cloning an animal requires that researchers first remove the nucleus of an egg cell. When researchers do this, they also remove proteins that are essential to help cells divide, Lanza said. In mice, this isn’t a problem, because the embryo that is ultimately created is able to make these proteins again. But primates aren’t able to do this, and researchers think it may be one reason that attempts to clone monkeys have failed, Lanza said. [See How Stem Cell Cloning Works (Infographic)]

What’s more, cloned animals often have different kinds of genetic abnormalities that can prevent embryo implantation in a uterus, or cause the fetus to spontaneously abort, or the animal to die shortly after birth, Lanza said.

These abnormities are common because cloned embryos have just one parent rather than two, which means that a molecular process known as “imprinting” does not occur properly in cloned embryos, Lanza said. Imprinting takes place during embryo development, and selectively silences certain genes from one parent or the other.

Problems with imprinting can result in extremely large placentas, which ultimately leads to problems with blood flow for the fetus, Lanza said. In one experiment, Lanza and colleagues cloned a species of cattle called banteng, and it was born at twice the size of a normal banteng. It had to be euthanized, Lanza said.

The extremely high rate of death, and the risk of developmental abnormities from cloning makes cloning people unethical, Lanza said.

“It’s like sending your baby up in a rocket knowing there’s a 50-50 chance it’s going to blow up. It’s grossly unethical,” Lanza said.

Read more: http://www.foxnews.com/science/2013/05/19/could-humans-be-cloned/#ixzz2TnzBJH7Y

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