Interesting Research done at University of Washington

Extra chromosome 21 removed from Down syndrome cell line

University of Washington scientists have succeeded in removing the extra copy of chromosome 21 in cell cultures derived from a person with Down syndrome, a condition in which the body’s cells contain three copies of chromosome 21 rather than the usual pair.

A triplicate of any chromosome is a serious genetic abnormality called a trisomy. Trisomies account for almost one-quarter of pregnancy loss from spontaneous miscarriages, according to the research team. Besides Down syndrome (trisomy 21), some other human trisomies are extra Y or X chromosomes, and Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13), both of which have extremely high newborn fatality rates.

In their report appearing in the Nov. 2 edition of Cell Stem Cell, a team led by Dr. Li B. Li of the UW Department of Medicine described how they corrected trisomy 21 in human cell lines they grew in the lab.  The senior scientists on the project were gene therapy researchers Dr. David W. Russell, professor of medicine and biochemistry, and Dr. Thalia Papayannopoulou, professor of medicine.

The targeted removal of a human trisomy, they noted, could have both clinical and research applications.

In live births, Down syndrome is the most frequent trisomy. The condition has characteristic eye, facial and hand features, and can cause many medical problems, including heart defects, impaired intellect, premature aging and dementia, and certain forms of leukemia, a type of blood cancer.

“We are certainly not proposing that the method we describe would lead to a treatment for Down syndrome,” Russell said.  “What we are looking at is the possibility that medical scientists could create cell therapies for some of the blood-forming disorders that accompany Down syndrome.”

For example, he said, someday Down syndrome leukemia patients might have stem cells derived their own cells, and have the trisomy corrected in these lab-cultured cells.  They could then receive a transplant of their own stem cells – minus the extra chromosome – or healthy blood cells created from their fixed stem cells and that therefore don’t promote leukemia, as part of their cancer care.

He added that the ability to generate stem cells with and without trisomy 21 from the same person could lead to better understanding of how problems tied to Down syndrome originate.  The cell lines would be genetically identical, except for the extra chromosome. Researcher could contrast, for example how the two cell lines formed brain nerve cells, to learn the effects of trisomy 21 on neuron development, which might offer insights into the lifelong cognitive impairments and adulthood mental decline of Down syndrome. Similar comparative approaches could seek the underpinnings of untimely aging or defective heart tissue in this genetic condition.

The formation of trisomies is also a problem in regenerative medicine research using stem cells. Russell and his team observed that their approach could also be used to revert the unwanted trisomies that often arise in creating stem cell cultures.

Figuring out the exact techniques for removing the extra chromosome was tricky, Russell said, but his colleague Li worked hard to solve several challenges during his first attempts at deriving the engineered cell lines.

“Dr. Li’s achievement was a tour de force,” Russell said.

The researchers used an adeno-associated virus as a vehicle to deliver a foreign gene called TKNEO into a particular spot on chromosome 21, precisely within a gene called APP, which sits on the long arm of the chromosome.  The TKNEO transgene was chosen because of its predicted response to positive and negative selection in specific laboratory growth mediums.  When grown in conditions that selected against TKNEO, the most common reason for cells to survive was the spontaneous loss of the chromosome 21 harboring the transferred gene. Other survival tactics were point mutations, which are single, tiny alterations in DNA base pairs; gene silencing, which meant TKNEO was “turned off” by the cell; or deletion of the TKNEO.

Russell explained a key advantage of this technique for getting rid of the entire extra chromosome: Once it was gone, nothing was left behind.

“Gene therapy researchers have to be careful that their approaches do not cause gene toxicity,” he said. This means, for example, that removal of a chromosome must not break or rearrange the remaining genetic code. This method shouldn’t do that.”

Other researchers on this study were Kai-Hsin Chang, Pei-Rong Wang and Roli K. Hirata. The project was supported by grants from Horizon Discovery and from the National Institutes of Health (DK55759, HL53750,GM086497, DK077864, and HL46557.)  The researchers declared no financial conflicts of interest.


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Dr. Julia Kinder & A Petition to Medical Schools

I received an email about 10 days ago and just kept forgetting to look at it with much detail. I took a look at it today and while it's not Down Syndrome Awareness Month still, thought it would be good to share nonetheless. 

Celebrate the UPside of Down™ during National Down Syndrome

Awareness Month: Dispelling Myths and Smashing Stereotypes

Dr. Julia Kinder is celebrating National Down Syndrome Awareness Month with a Sweepstakes,

Photo Contest, and a Petition to Medical School Faculty across the United States.

Cape Girardeau, MO – October 18, 2012 – Dr. Julia Kinder, practicing physician, national speaker, and an advocate for children with special needs, is celebrating National Down Syndrome Awareness Month with an online Photo Contest, Sweepstakes, and a very important Petition. These can be found on her website, www.JuliaKinder.com. The photo contest gives families of children with Down syndrome an avenue for showcasing their child’s abilities. The sweepstakes offers fun awareness products created by Dr. Kinder while drawing attention to dispelling the myths and stereotypes surrounding Down syndrome.  The newly launched petition calls upon medical schools to provide more training on Down syndrome.

“No parent should feel like their baby's life starts out with a death; the death of their dreams for the future, the end of their hope for a happy, healthy child,” said Dr. Kinder, owner of JuliaKinder.com. “But it happens every day, because physicians who deliver the diagnosis of Down syndrome often give inaccurate, incomplete, and negative information that intensifies the unfounded fear of this diagnosis.”

Currently physicians do not receive training on giving the diagnosis of Down syndrome in a productive way, according to Dr. Kinder. Nor do they learn of needed resources for parents and baby. Medical education focuses on the possible health and learning issues, which not every child will encounter. Physicians do not understand what a child with Down syndrome is like outside of the medical aspects. What is crucial to every baby with Down syndrome is that they begin receiving early intervention and therapy immediately. Medical education does not cover this topic, therefore, physicians are missing a crucial piece of information to pass along to new parents.

Dr. Kinder has been a practicing physician for the past decade. However, eight years ago when her daughter was born with Down syndrome, she discovered her medical training did nothing to prepare her for raising a child with Down syndrome.

“Ella is completely healthy and smart, which contradicts everything I learned about Down syndrome,” said Dr. Kinder. “Medical school taught me about a laundry list of health problems and mental retardation, none of which applied to my child. I had no practical information on how to take care of her. I didn’t know she needed to start therapy immediately. When she was born, the doctors and hospital gave me no information or resources. I left the hospital without so much as a pamphlet.”

According to Dr. Kinder, the information on Down syndrome that doctors give to new parents tends to focus on the potential medical and learning problems. Doctors have not been trained to explain to these new parents that a child with Down syndrome is more like other children than they are different, and that many of the medical issues never materialize. Parents leave the hospital with the impression that their child’s prospects for a happy, healthy, and fulfilled life are grim. Unfortunately, many parents admit they struggled to connect emotionally with their baby during those first few months, as if unconsciously attempting to prepare for some awful manifestation of the diagnosis.

“I have decided to tackle this issue head-on,” states Dr. Kinder. “It is unacceptable for the medical community to contribute to a new parent’s fear of their own baby. This negative emotional state can prevent parents from providing the appropriate care their newborn needs. Babies with Down syndrome must start early intervention and therapy immediately - it should not be delayed because doctors fail to give parents complete and accurate information, along with resources for support.”

Dr. Kinder has spent eight years speaking to the medical community, future teachers and therapists, and to the general public regarding Down syndrome, as well as counseled hundreds of new parents. In 2009 Dr. Kinder began blogging on the topic, giving new parents hope and direction. She has devised fun ways to dispel the myths and darkness by promoting positive phrases such as “My kid has more Chromosomes than yours” as well as the “UPside of Down” concept. She encourages others to proudly display the UPside of Down with car decals, shirts, bracelets, and other awareness products that she has developed. Dr. Kinder has created a tribe of families who support each other and spread awareness. Their motto is, “Go beyond just surviving [with Down syndrome] to Thriving - become a Thrivalist!”

“I want to show the world the UPside of Down syndrome and I want to improve the education medical students receive on helping new parents,” said Dr. Kinder. “My ultimate goal is for the birth of every baby with Down syndrome to be celebrated, and for every baby to receive the care required to maximize their developmental potential.”

To get involved and sign Dr. Kinder’s petition please go to www.JuliaKinder.com/petition/. To learn more about her website’s Down Syndrome Awareness Month activities and to participate in the celebration, please visit http://www.JuliaKinder.com/DownSyndromeCelebration/.

About Dr. Julia Kinder

Dr. Julia A. Pewitt Kinder is an accomplished national speaker, early childhood education advocate, author and practicing physician. She and husband Mitch reside in Cape Girardeau, Mo., with their three children, Ella and twin boys Paxton and Dexter.  Dr. Kinder is licensed to practice in both Missouri and Texas and is in private practice with her brother in Jackson, Missouri. She also serves as a hospice physician for Tri-County Hospice. In addition, Dr. Kinder is a certified fitness instructor and promotes easy ways to incorporate exercise into daily routines. More information about Dr. Kinder can be found on her website at www.JuliaKinder.com.

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