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From skin to brain: Stem cells without genetic modification – Phys.Org

March 15, 2017 by Grove Potter The four images, from left to right, show Keratinocyte-derive neural crest stem cells turning into neurons as shown by typical neuronal morphology. Credit: University at Buffalo.

A discovery, several years in the making, by a University at Buffalo research team has proven that adult skin cells can be converted into neural crest cells (a type of stem cell) without any genetic modification, and that these stem cells can yield other cells that are present in the spinal cord and the brain.

The practical implications could be very significant, from studying genetic diseases in a dish to generating possible regenerative cures from the patient's own cells.

"It's actually quite remarkable that it happens," says Stelios T. Andreadis, PhD, professor and chair of UB's Department of Chemical and Biological Engineering, who recently published a paper on the results in the journal Stem Cells.

The identity of the cells was further confirmed by lineage tracing experiments, where the reprogrammed cells were implanted in chicken embryos and acted just as neural crest cells do.

Stem cells have been derived from adult cells before, but not without adding genes to alter the cells. The new process yields neural crest cells without addition of foreign genetic material. The reprogrammed neural crest cells can become smooth muscle cells, melanocytes, Schwann cells or neurons.

"In medical applications this has tremendous potential because you can always get a skin biopsy," Andreadis says. "We can grow the cells to large numbers and reprogram them, without genetic modification. So, autologous cells derived from the patient can be used to treat devastating neurogenic diseases that are currently hampered by the lack of easily accessible cell sources."

The process can also be used to model disease. Skin cells from a person with a genetic disease of the nervous system can be reprogrammed into neural crest cells. These cells will have the disease-causing mutation in their chromosomes, but the genes that cause the mutation are not expressed in the skin. The genes are likely to be expressed when cells differentiate into neural crest lineages, such as neurons or Schwann cells, thereby enabling researchers to study the disease in a dish. This is similar to induced pluripotent stem cells, but without genetic modification or reprograming to the pluripotent state.

The discovery was a gradual process, Andreadis says, as successive experiments kept leading to something new. "It was one step at a time. It was a very challenging task that took almost five years and involved a wide range of expertise and collaborators to bring it to fruition," Andreadis says. Collaborators include Gabriella Popescu, PhD, professor in the Department of Biochemistry in the Jacobs School of Medicine and Biomedical Sciences at UB; Song Liu, PhD, vice chair of biostatistics and bioinformatics at Roswell Park Cancer Institute and a research associate professor in biostatistics UB's School of Public Health and Health Professions; and Marianne Bronner, PhD, professor of biology and biological engineering, California Institute of Technology.

Andreadis credits the persistence of his then-PhD student, Vivek K. Bajpai, for sticking with it.

"He is an excellent and persistent student," Andreadis says. "Most students would have given up." Andreadis also credits a seed grant from UB's office of the Vice President for Research and Economic Development's IMPACT program that enabled part of the work.

The work recently received a $1.7 million National Institutes of Health grant to delve into the mechanisms that occur as the cells reprogram, and to employ the cells for treating the Parkinson's-like symptoms in a mouse model of hypomyelinating disease.

"This work has the potential to provide a novel source of abundant, easily accessible and autologous cells for treatment of devastating neurodegenerative diseases. We are excited about this discovery and its potential impact and are grateful to NIH for the opportunity to pursue it further," Andreadis said.

The research is described in the journal Stem Cells under the title "Reprogramming Postnatal Human Epidermal Keratinocytes Toward Functional Neural Crest Fates."

Explore further: Embryonic gene Nanog reverses aging in adult stem cells

More information: Vivek K. Bajpai et al, Reprogramming Postnatal Human Epidermal Keratinocytes Toward Functional Neural Crest Fates, STEM CELLS (2017). DOI: 10.1002/stem.2583

Journal reference: Stem Cells

Provided by: University at Buffalo

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Scientists at the University of Newcastle, UK, have used a combination of small molecules to turn cells isolated from human skin into Schwann cells - the specialised cells that support nerves and play a role in nerve repair. ...

Johns Hopkins stem cell biologists have found a way to reprogram a patient's skin cells into cells that mimic and display many biological features of a rare genetic disorder called familial dysautonomia. The process requires ...

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A discovery, several years in the making, by a University at Buffalo research team has proven that adult skin cells can be converted into neural crest cells (a type of stem cell) without any genetic modification, and that ...

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From skin to brain: Stem cells without genetic modification - Phys.Org

Study identifies molecular clues for age-related intestinal issues – Medical Xpress

March 14, 2017 These microscopic images show structural changes in the intestine of an older mouse approaching 2 years of age (right) compared to intestine from a young 2-3 month old mouse (left). The older intestine has a smaller number of intestinal crypts (mucosal glands) that are wider. Researchers report in Cell Reports that intestinal stem cells (ISCs) age along with the animals, causing detrimental changes to intestinal structures and their function. They also show function can be restored by reactivating the signaling of a key molecule lost in aging intestinal stem cells. Credit: Cincinnati Children's

Intestinal stem cells rejuvenate daily so bowels will stay healthy and function normally, but a new study in Cell Reports suggests they also age along with people and lose their regenerative capacity.

Reporting their data online March 14, researchers suggest that reactivating the signaling of a key molecule lost in aging intestinal stem cells could restore healthy intestinal function in older people. The study was conducted in mice and human intestinal organoids by scientists at Cincinnati Children's Hospital Medical Center and the Institute for Molecular Medicine, Stem Cells and Aging at the University of Ulm in Germany.

Researchers say their study is the first to indicate that intestinal stem cells - which allow different intestinal cell types to renew themselves - age as people do. It also is the first to provide clear evidence that diminished signaling in intestinal stem cells (ISCs) by the Wnt protein - which is important to cell proliferation and renewal - drives the aging process and loss of ISCs' ability to rejuvenate intestinal tissues.

"Deterioration of Wnt signaling in aging intestinal stem cells may help explain imbalances in food and nutrient absorption in older people, but our paper also shows that biology allows us to reverse this process by restoring Wnt signaling," said Hartmut Geiger, PhD, senior investigator of the study. "Pharmacologic interventions will still need to be designed based on this finding, but we know now where to start."

Geiger is a member of the Division of Experimental Hematology and Cancer Biology at Cincinnati Children's.

Old vs. Young

In tests that compared the intestines of young mice (2 to 3 months old) with those of aged mice (approaching 2 years old), researchers noticed significant differences in the structural architecture of intestine.

Intestines from older mice showed a reduced number of crypts (mucosal glands), and the structures were longer and wider than in younger animals. Older intestines also had longer villi (absorptive tissues) and an elevated number of cells. But the researchers also noticed there were fewer numbers of actively dividing cells in the intestines of the older mice.

Study authors then looked for different characteristics in the ISCs of young and old mouse intestines. Although they did not observe differences in the numbers of ISCs, they did see a decreased presence of molecular markers that denote ISC function. This led them to conclude that ISC function diminishes in older intestines.

Finding Wnt

To identify genetically driven molecular processes that prompt aging and diminished function in ISCs (and in Paneth and goblet cells they form) the researchers subjected ISCs to RNA sequencing analysis. These tests showed significant reductions in gene expression in the older cells, including the down regulation of molecular pathways involving the genes PPAR, SMAD and Wnt.

Because Wnt plays a particularly prominent role in regulating ISCs, the researchers focused on this pathway. In young and old mice they tested the presence and strength of the Wnt signaling pathway in cells of the mesenchyme - which forms connective and skeletal tissues. The mesenchyme has recently been identified in other studies as providing a supportive environment for ISCs to form.

The authors also tested Wnt signaling in different intestinal cells from young and old mice, specifically goblet and Paneth cells that secrete proteins and antimicrobial peptides that are important to sustaining healthy intestines. In both instances they observed a decline in Wnt in intestinal tissues from the older animals.

In testing on lab-generated human and mouse intestinal organoids, the researchers also observed declines in Wnt signaling in older intestines along with altered intestinal structures and indications of diminished function.

Molecular restoration

Researchers concluded their study by testing the restoration of Wnt signaling in intestines by adding Wnt3a (an inducer of Wnt signaling) in aged mouse and human organoid models, which were generated with donated human cells. This rejuvenated the regenerative potential of ISCs in the mouse and human modeling systems. It also boosted the generation of Paneth and goblet cells and prompted an increase in the number of intestinal crypts and other critical structures.

The scientists are following up the current study by trying to define the extent to which therapeutic intervention to rejuvenate ISCs might be beneficial to humans.

Explore further: Scientists wage fight against aging bone marrow stem cell niche

More information: "Canonical Wnt Signaling Ameliorates Aging of Intestinal Stem Cells" Cell Reports, DOI: 10.1016/j.celrep.2017.02.056, http://www.cell.com/cell-reports/fulltext/S2211-1247(17)30254-1

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Study identifies molecular clues for age-related intestinal issues - Medical Xpress

City of Hope Hosts Second California Institute for Regenerative Medicine Alpha Stem Cell Clinics Symposium – Business Wire (press release)

DUARTE, Calif.--(BUSINESS WIRE)--The stories of patients who have benefited from stem cell therapies funded by the California Institute for Regenerative Medicine (CIRM) will be highlighted at the second symposium of the institutes Alpha Stem Cell Clinics Network on Thursday, March 23, at City of Hope.

CIRM, the states stem cell agency, has developed a network of Alpha Stem Cell Clinics that are focused on innovative stem cell-based therapies. The network, which consists of three clinics located at City of Hope, UCSD, and UCLA/UC Irvine, will showcase its most successful clinical trials at the daylong symposium.

Scientists, clinicians, patient advocates, and business and insurance experts, as well as CIRM and City of Hope representatives, are hosting the meeting to address various aspects of making more stem cell therapies a reality for patients.

CIRMs Alpha Clinics are working day in and day out to find cures for such debilitating diseases as glioblastoma, leukemia and other cancers, as well as blinding eye diseases, spinal cord injuries, HIV, hemophilia, diabetes and other catastrophic conditions for which there are no current cures, said John A. Zaia, M.D., the Aaron D. Miller and Edith Miller Chair in Gene Therapy, who is also director of the Center for Gene Therapy and principal investigator of City of Hopes Alpha Stem Cell Clinic. This symposium brings us together to share the advancements weve made in delivering stem cell treatments to patients, and to discuss how we can accelerate their development.

Highlights of Alpha Clinics: Making the Future a Reality for Stem Cell-Based Therapies

Registration starts at 7 a.m. There will be a welcome address at 8 a.m. with panels concluding at 5 p.m. View the schedule here.

About City of Hope

City of Hope is an independent research and treatment center for cancer, diabetes and other life-threatening diseases. Designated as one of only 47 comprehensive cancer centers, the highest recognition bestowed by the National Cancer Institute, City of Hope is also a founding member of the National Comprehensive Cancer Network, with research and treatment protocols that advance care throughout the world. City of Hope is located in Duarte, California, just northeast of Los Angeles, with communityclinics throughout Southern California. It is ranked as one of "America's Best Hospitals" in cancer by U.S. News & World Report. Founded in 1913, City of Hope is a pioneer in the fields of bonemarrowtransplantation, diabetes and numerous breakthrough cancer drugs based on technology developed at the institution. For more information about City of Hope, follow us on Facebook, Twitter, YouTube or Instagram.

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City of Hope Hosts Second California Institute for Regenerative Medicine Alpha Stem Cell Clinics Symposium - Business Wire (press release)

The tip of the iceberg: A look at stem cell science at Stanford – Scope (blog)

For outsiders, its easy to get confused about the status of stem cell science. If you have questions, a recentStanford Magazine article offers a reader-friendlyentre.

The piece introduces the pioneering work of Irving Weissman, MD, who was the first researcher to isolate stem cells from adult tissue. And it highlights the amazing outcomefrom a recent clinic trial on stem cell therapy for stroke led by neurosurgeonGary Steinberg, MD, PhD. One woman who used a wheelchair often before the procedure no longer needed it following the procedure. As Steinberg saidin the article:

This was a huge surprise We thought the circuits were dead or irreversibly injured, but theyre clearly not; they can be resurrected. Were still trying to figure out exactly how we are resurrecting them.

Maria Grazia Roncarolo, MD, co-director of theInstitute of Stem Cell Biology and Regenerative Medicine, is one of the researchers working to bring the innovative basic science work taking place at Stanford into the clinic.

My mission is to help the university to build a brand in stem cell therapy, sheexplained. What we are now pushing into the clinic is just the tip of the iceberg But what we really want to build is a translational research program that would allow all the potential stem cell therapies to surface and be offered to patients in need.

Previously: Stem cells create faithful replicas of native tissue, according to Stanford study, Stroke of luck: Stem-cell transplants show strong signs of efficacy in clinical safety trial for strokeand Stanford scientists describe stem-cell and gene-therapy advances in scientific symposium Image by Ghanson

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The tip of the iceberg: A look at stem cell science at Stanford - Scope (blog)

US Stem Cell Inc (OTCMKTS:USRM) Finding Support After … – Street Register

Shares of US Stem Cell Inc (OTCMKTS:USRM) began to stabilize this week on the heels of a rather large consolidation that affected the stock over a period of several trading days following its huge February price explosion.

From February 1st to March 1st, USRM shares traded from a low of .0024 all the way up to .0599, which represents a dizzying increase of 2395% while volume during that same period was as high as it had ever been over the life of the stock. In the week to follow, USRM would see an unsurprising pull back off of that impressive high, and appears to have found support for the time being.

US Stem Cell Inc (OTCMKTS:USRM) published a PR earlier in the week alluding to the appointment of a new board member- one who had a preexisting relationship with the company. You can read more about that appointment further down the page.

About US Stem Cell

US Stem Cell, Inc. is an emerging enterprise in the regenerative medicine / cellular therapy industry. It is focused on the discovery, development and commercialization of cell based therapeutics that prevent, treat or cure disease by repairing and replacing damaged or aged tissue, cells and organs and restoring their normal function. The companys business, which includes three operating divisions (US Stem Cell Training, Vetbiologics and US Stem Cell Clinic) includes the development of proprietary cell therapy products as well as revenue generating physician and patient based regenerative medicine / cell therapy training services, cell collection and cell storage services, and the operation of a cell therapy clinic. Management maintains that revenues and their associated cash in-flows generated from the businesses will, over time, provide funds to support clinical development activities. The company believes the combination of its own therapeutics pipeline combined with its revenue generating capabilities provides a unique opportunity for growth and a pathway to profitability.

US Stem Cell Appoints New Board Member

This week, the US Stem Cell announced that Greg Knutson, the Manager of NorthStar Biotech, LLC, has joined the Board of Directors of U.S. Stem Cell, Inc.

We are very pleased that Greg Knutson, a longtime supporter of the U.S. Stem Cell family of companies, has agreed to join our Board and assist us to continue with our recent technological advances and financial accomplishments, said Mike Tomas, President and CEO of U.S. Stem Cell, Inc.

A longtime U.S. Stem Cell shareholder and supporter, Knutson brings more than 30 years of business and financial experience to the organization. During his entrepreneurial career, Knutson founded Concrete Specialists, Inc. and continues to serve as its President; is the founder and current President of Sunwood Properties; and is the founder and Managing Partner of G&G Land Development, LLC.

Demonstrating a progressive step forward, Knutson joins the Board of Directors just as the two companies amicably settled a legal dispute related to NorthStars preferred shares. (Source: Accesswire)

On a clear downside, USRM has a miniscule market value of just $1.6 million at current pricing. That being said, the sheer intensity of the mega-run we witnessed in February and the fact that the PPS appears to be stabilizing after a large consolidation, is enough to keep our interest. At whatever point the stock ultimately launches a solid recovery, there will almost certainly be opportunities opening up for traders. Were going to continue to track USRM and its progress on the chart, and keep a sharp eye out for new updates. Stay up to date on USRM right here on Street Register. We encourage you to sign up for our 100% free penny stock newsletter, by simply submitting your active email address in the box

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US Stem Cell Inc (OTCMKTS:USRM) Finding Support After ... - Street Register

Stem Cells Used to Create Artificial Embryo for the First Time Ever – TrendinTech

A team of scientists from the University of Cambridge has made revolutionary news because for the first time ever an artificial mouse embryo has been grown using stem cells. This is fantastic news for the researchers as understanding the beginning stages of embryo formation could prove essential in understanding what two thirds of all human pregnancies fail at this time.

While attempting to grow embryos is not a new feat, its one thats had very limited success over the years. This is mainly due to the fact that early embryo development needs different cell types to work closely with one another. However, the new study demonstrates how embryos can actually be grown using a combination of genetically-modified mouse ESCs and TSCs along with an extracellular matrix.

Both the embryonic and extra-embryonic cells start to talk to each other and become organized into a structure that looks like and behaves like an embryo, said Professor Magdalena Zernicka-Goetz, leader of the research. She continues, It has anatomically correct regions that develop in the right place and at the right time. We knew that interactions between the different types of stem cell are important for development, but the striking thing that our new work illustrates is that this is a real partnership these cells truly guide each other. Without this partnership, the correct development of shape and form and the timely activity of key biological mechanisms doesnt take place properly.

As part of the research the team was able to show how stem cells are organized, with ESCs and TSCs at separate ends, and followed the same pattern of development to that of a human embryo. But, without the third form of stem cell, the one that would allow development of the yolk sac, its unlikely the embryo would ever develop into a healthy fetus. Also the actual system itself is not yet designed to be able to develop placenta.

Zernicka-Goetz believes that one of her recently developed techniques will enable researchers to for the first time ever gain a real insight into the first initial stages if human embryo development. She says, We think that it will be possible to mimic a lot of the developmental events occurring before 14 days using human embryonic and extra-embryonic stem cells using a similar approach to our technique using mouse stem cells. We are very optimistic that this will allow us to study key events of this critical stage of human development without actually having to work on embryos. Knowing how development normally occurs will allow us to understand why it often goes wrong.

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Stem Cells Used to Create Artificial Embryo for the First Time Ever - TrendinTech

The First 3D Structure of Active DNA could advance Stem Cell Therapies – Labiotech.eu (blog)

Scientists from the University of Cambridge have determined the first 3D structures of mammalian genomes from individual cells.

For the first time, researchers from the University of Cambridge were able to determine the 3D structure of an active mouse genome in embryonic stem cells. Tim Stevens and his colleagues used a combination of imaging and measurements that reveal DNA interactionsto unravel how the DNA is folded together.This could lead tonew insights into the regulation of gene expression in health and disease.

Every cell in our body contains the same DNA molecules and thusthe same set of genes. Still,our blood cells differ fundamentally from our skin cells. The basis for this isgene regulation, meaning that different cells will not express every gene encoded on our DNA but only a specific subset.

An exciting new avenue for our understanding of gene regulation is the importance of the 3D DNA structure. Regulatory regions within our DNA play a major role in regulating gene expression, but arequirement is that the regions come into spatial contact with the associated genes.

It is well known today, that the way the DNA is folded within the cell is tightlyregulated and determines the contact between different regulatory regions with different genes and thereby determines which genes areswitched on or off.

By looking at individual stem cells, the researchers willnow be able to better understandhowthese master cells are able to differentiate into different cell types of our body, which could revolutionize regenerative medicine.

Knowing where all the genes and control elements are at a given moment will help us understand the molecular mechanisms that control and maintain their expression. () Currently, these mechanisms are poorly understood and understanding them may be key to realizingthe potential of stem cells in medicine.says Prof Ernest Laue, who supervised the study.

A better understanding of how the genome structure determines whether genes are switched on or off could also be important to understand what happens in cancer. Abnormal genomes might cause changes in DNA folding and thereby lead to abnormal gene expression.

Changes in gene expression which are not based on the DNA sequence are calledepigenetic modifications. Epigenetics is definitely one of the recent hypes within the cancer field.The folding of DNA is only one aspect of epigenetic gene regulation, while direct modifications of the DNA or DNA-associated proteins provide another. Cancer cells often make use of the epigenetic machinery to change gene regulation and support their survival.

A recent study,for example, unveiled the role of epigenetic changes in driving pancreatic cancer metastasis. By understanding what happens on the gene regulatorylevel, the researchers were able to find a compound, which specifically inhibits these epigenetic changes and therebycancer cell progression.

Epigenetic mechanisms definitely play a key role not only to advance our understanding of stem cell commitment and regenerative medicine, but also in disease areas such as cancer research. You can findthe identified 3D structures of the DNA below.

Images via shutterstock.com /Iaremenko Sergii

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The First 3D Structure of Active DNA could advance Stem Cell Therapies - Labiotech.eu (blog)

RepliCel’s autologous cell therapy candidate to treat hair loss safe in long-term study; shares ease 5% on long … – Seeking Alpha

Thinly traded nano cap ReliCel Life Sciences (OTCQB:REPCF -5.1%) slips after it announced data from a five-year Phase 1 study assessing the safety of its autologous cell therapy for the treatment of androgenic alopecia (pattern baldness), RCH-01. The results were fine, but the timeline for the next study has apparently dampened investors' enthusiasm.

The 19-subject trial met its endpoints thereby confirming the complete safety profile of a high dose of dermal sheath cup cells, administered via injection, for patients with pattern baldness.

Although not powered for efficacy, a treatment effect was observed. The seven best responders experienced at least a 10% increase versus baseline in hair density six months after injection. At month 24, the average hair density increase in the same seven subjects was 8.3%. The top responder showed a 21% increase in hair density at month 24.

The company intends to advance RCH-01 into a Phase 2 study in 160 healthy men with mild-to-moderate pattern baldness. Dermal sheath cup cells will be isolated from a small punch biopsy taken from the back of the subject's scalp. The cells will be replicated and then reintroduced into balding areas. Participants will remain on study for ~39 months.

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RepliCel's autologous cell therapy candidate to treat hair loss safe in long-term study; shares ease 5% on long ... - Seeking Alpha

Stem Cell Therapy | Runner’s World – Runner’s World


Runner's World

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Stem Cell Therapy | Runner's World - Runner's World

Some Genetic Variations Difficult to Evaluate Using Current Stem Cell Modeling Techniques – Bioscience Technology

Some heritable but unstable genetic mutations that are passed from parent to affected offspring may not be easy to investigate using current human-induced pluripotent stem cell (hiPSC) modeling techniques, according to research conducted at The Icahn School of Medicine at Mount Sinai and published March 14, in the journalStem Cell Reports. The study serves to caution stem cell biologists that certain rare mutations, like the ones described in the study, are difficult to recreate in laboratory-produced stem cells.

Stem cell-based disease modeling involves taking cells from patients, such as skin cells, and introducing genes that reprogram the cells into human-induced pluripotent stem cells (hiPSCs). These "master cells" are unspecialized, meaning they can be pushed to become any type of mature cell needed for research, such as skin, liver or brain. The hiPSCs are capable of renewing themselves over a long period of time, and this emerging stem cell modeling technique is helping elucidate the genetic and cellular mechanisms of many different disorders.

"Our study describes how a complex chromosomal rearrangement genetically passed by a patient with psychosis to her affected son was not well recreated in laboratory-produced stem cells," says Kristen Brennand, Ph.D, Associate Professor of Genetics and Genomic Sciences, Neuroscience, and Psychiatry at the Icahn School of Medicine, and the study's senior investigator. "As stem cell biologists dive into studying brain disorders, we all need to know that this type of rare mutation is very hard to model with induced stem cells."

To investigate the genetic underpinnings of psychosis, the research team used hiPSCs from a mother diagnosed with bipolar disease with psychosis, and her son, diagnosed with schizoaffective disorder. In addition to the normal 46 chromosomes (23 pairs), the cells in mother and son had a very small extra chromosome, less than 1/10th normal size. This microduplication of genes is increasingly being linked to schizophrenia and bipolar disorders, and the extra chromosomal bit, known as a marker (mar) element, falls into the category of abnormally duplicated genes.

For the first time, the Mount Sinai research team tried to make stem cells from adult cells with this type of mar defect. Through the process, they discovered that the mar element was frequently lost during the reprogramming process.

While mar elements in the general population are rare (less than .05 percent in newborn infants), more than 30 percent of individuals with these defects are clinically abnormal, and mar elements are also significantly more likely to be found in patients with developmental delays.

The study found that the mother's cells were mosaic, meaning some cells were normal while others were not, and the hiPSCs the team created accurately replicated that condition: some were normal and some had the extra mar chromosome. But the technique did not work well with the son's cells. While all of his cells should have had the mar element, as with his mother, some of the reprogrammed stem cells did not contain the extra bit of chromosome.

"We realized we kept losing the mutation in the stem cells we made, and the inability to recreate cells with mar elements may hamper some neuropsychiatric research," says Dr. Brennand. "The bottom line is that it is essential that stem cell biologists look for existing mar elements in the cells they study, in order to check that they are retained in the new stem cells."

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Some Genetic Variations Difficult to Evaluate Using Current Stem Cell Modeling Techniques - Bioscience Technology