Thursday, February 27th, 2014
A fertility treatment in which the genetic material of three different people are combined to create an embryo that is free of certain genetic defects is under scrutiny by the Food and Drug Administration amid claims that the therapy could amount to creating “designer babies.” More on the ethically complex method from The New York Times:
The agency has asked a panel of experts to summarize current science to determine whether the approach — which has been performed successfully in monkeys by researchers in Oregon and in people more than a decade ago — is safe enough to be used again in people.
The F.D.A. meeting, on Tuesday and Wednesday, is meant to address the scientific issues around the procedure, not the ethics. Regulators are asking scientists to discuss the risks to the mother and the potential child and how future studies should be structured, among other issues. The meeting is being closely watched. The science of such therapies has advanced significantly in recent years, and many scientists are urging federal regulators to ease requirements for study in humans.
The procedure in question involves mitochondria, the power producers in cells that convert energy into a form that cells can use. Mitochondria with defects that could be passed to a fetus are replaced with healthy mitochondria from another woman. This is done either before or after an egg is fertilized.
Scientists have already experimented with combining genetic material from cells of three people. In 2001, researchers in New Jersey did so using material from the cytoplasm, the material that surrounds the nucleus of the egg and directs its development after fertilization, from fertile women into the eggs of infertile women. More than 17 babies have been born this way in the United States.
The practice raised questions and eventually led the F.D.A. to tell researchers that they could not perform such procedures in humans without getting special permission from the agency. Since then, studies have been confined to animals.
But a researcher in Oregon, Shoukhrat Mitalipov, has performed the mitochondrial procedure in monkeys and has said that it is ready to be tried in people.
Such genetic methods have been controversial in the United States, where critics and some elected officials wonder how far scientists plan to go in their efforts to engineer humans, and question whether these methods might create other problems.
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Tuesday, February 4th, 2014
The debate over the morality of performing genetic tests on embryos–and deciding not to use those carrying deadly genetic disorders for potential pregnancies–continues, as a New York Times report explains:
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….The procedure also raises unsettling ethical questions that trouble advocates for the disabled and have left some doctors struggling with what they should tell their patients. When are prospective parents justified in discarding embryos? Is it acceptable, for example, for diseases like GSS [Gerstmann-Straussler-Scheinker disease], that develop in adulthood? What if a gene only increases the risk of a disease? And should people be able to use it to pick whether they have a boy or girl? A recent international survey found that 2 percent of more than 27,000 uses of preimplantation diagnosis were made to choose a child’s sex.
In the United States, there are no regulations that limit the method’s use. The Society for Assisted Reproductive Technology, whose members provide preimplantation diagnosis, says it is “ethically justified” to prevent serious adult diseases for which “no safe, effective interventions are available.” The method is “ethically allowed” for conditions “of lesser severity” or for which the gene increases risk but does not guarantee a disease.
There is no question that the method’s use is increasing rapidly, though no group collects comprehensive data, said Dr. Joe Leigh Simpson, vice president for research at the March of Dimes and past president of the American Society for Reproductive Medicine.
Monday, December 9th, 2013
Fifteen-year-old Hayley Mogul and her 9-year-old sister both extremely rare genetic disorders–so rare, that a cure isn’t even being sought by scientists–that has had severe neurological and metabolic consequences for the sisters. But their participation in cutting edge research that combines stem cell and genetic techniques may give hope to future generations. NBC News reports:
There’s no cure for their rare disorders, caused by unique genetic mutations. But for once, there’s an advantage to having conditions so rare that drug companies cannot even think of looking for a cure. The sisters are taking part in a whole new kind of experiment in which scientists are literally turning back the clock on their cells.
They’re using an experimental technique to transform the cells into embryonic form, and then growing these baby cells in lab dishes.
The goal is the get the cells to misfire in the lab in just the same way they are in Hayley’s and Bari’s bodies. It’s a new marriage of genetics and stem cell research, and represents one of the most promising applications of so-called pluripotent stem cells.
“One day these two girls will probably change the face of medicine as we know it,” said their father, Steven Mogul.
Steven and Robyn Mogul don’t understand why both their daughters ended up with the rare mutations, which cause a range of neurological and metabolic problems.
“We have been tested,” said Mogul, a 45-year-old wealth manager living in Chicago. “We don’t have any mutations, and there are no developmental issues. We have no idea how it happened. “
The girls need special schooling and physical therapy. They must wear diapers, and when they get a cold or the flu, they can develop dangerously low blood sugar. “When the kids get sick, get colds or flu, we have to get them to the hospital,” Mogul said.
Hayley, 15, has a mutation in a gene called RAI1, which can cause Smith-Magenis syndrome. The syndrome affects 1 in 25,000 people and can disturb sleep patterns, cause obesity and behavioral issues. But Hayley’s mutation is unique and puzzling. Bari, 9, has an RAI1 mutation and a similarly unique mutation in the GRIN2B gene, which can cause learning disabilities.
“Bari doesn’t talk,” Mogul said. “She walks around, she gets around and lets you know what she wants. She is eating baby food and she is drinking from bottles.”
Hayley can attend school and can read, but lacks the fine motor skills needed to write. It’s especially unusual for two children in the same family to end up with such rare, and different, mutations.
Image: DNA, via Shutterstock
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Friday, September 20th, 2013
A genetic disorder that can lead to developmental delays, anxiety, and social awkwardness is misdiagnosed as an autism spectrum disorder (ASD) as much as 50 percent of the time, according to a new study by researchers at the University of California Davis. The mistake can lead to inappropriate treatment for the children, and may even worsen the symptoms of their genetic condition. More from Time.com:
About one in 2000 people are diagnosed with 22q11.2 deletion syndrome, which can lead to developmental delays, social awkwardness and anxiety, among other symptoms. Because those symptoms overlap with some of the hallmark signs of autism, researchers say that anywhere from 20% to 50% of children with 22q, as the condition is called, are misdiagnosed with autism.
That can have serious implications for these patients, since behavior-based treatments designed to alleviate the social deficits of autism may actually exacerbate anxiety among those with the 22q genetic disorder. If left untreated, children with 22q can be at higher risk of developing other mental health disorders like schizophrenia later in life.
To tease apart the differences between children with 22q and those with autism, the researchers, based at the University of California Davis MIND Institute, recruited a small group of 29 kids from a website the study called Cognitive Analysis and Brain Imaging Laboratory (CABIL). The scientists noticed that parents of children with the genetic disorder often commented that while their kids were diagnosed with autism, they seemed different from other children with the developmental disorder. “It’s quite clear that children with the [22q] disorder do have social impairments,” said study author Tony J. Simon, a professor of psychiatry and behavioral sciences at the MIND Institute in a statement. “But it did seem to us that they did not have a classic case of autism spectrum disorder. They often have very high levels of social motivation. They get a lot of pleasure from social interaction, and they’re quite socially skilled.”
So the team gave the children two of the gold standard tests for diagnosing autism — the Autism Diagnostic Observation Schedule (ADOS) and the Social Communication Questionnaire (SCQ) — to see if they indeed showed signs of autism.
Only five of the children had elevated scores on the ADOS test, and four out of the five had anxiety. None of the 22q children had scores high enough in both tests to classify them as having autism.
Image: Child with pediatrician, via Shutterstock
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Tuesday, June 11th, 2013
Omegaven, a medication developed at Boston Children’s Hospital to save the lives of infants who cannot absorb nutrition, is stuck in the FDA approval process, apparently causing delays that leave parents and doctors alike frustrated and worried. The drug is a crucial part of treatment for Microvillus Inclusion Disease, a rare genetic condition in which a child cannot absorb fluid or nutrients except through a direct injection of a treatment called total parenteral nutrition, or TPN. TPN, however, can cause liver damage over time; Omegaven counters that damaging effect. More from NBC News:
The potentially life-saving medication Omegaven, an intravenous mixture made with fish oil, reduces the fatal fat accumulation in children’s livers caused by TPN. Fish oil contains anti-inflammatory omega-3 fatty acids, which have been shown to prevent fat buildup.
It is unclear when or whether Omegaven will be approved. The normal FDA process for approval is to test medications in large trials that randomly assign patients to receive either the new drug or a placebo. In fatal illnesses, that can present doctors with a tough ethical quandary: Do you do the science right and potentially lose some patients or just keep treating patients in research studies.
Not daunted by the lack of FDA approval, Sam [O’Connor's] family signed him up for a Boston Children’s Hospital research study looking at the new medication’s efficacy.
It didn’t take long to see results.
“For me, it was . . . the personality change,” Debra said. “To have him start responding to me and playing, it’s just like he’s actually a person again. You know, it’s almost like his life started at that point because before it was just enduring.”
Now 5, Sam is one of the lucky ones because he was able to get the drug he needed. Other children aren’t so lucky, says Puder, who developed the Omegaven treatment after watching up to four children die from liver failure each year at his hospital alone.
Without FDA approval, Omegaven is available only to those who can come to Boston to take the drug in a research protocol, or at another hospital with special dispensation from the FDA, a provision called “compassionate use.”
Image: Doctor holding infant, via Shutterstock
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