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The amazing finding of senescent cells in embryos. Until now, these cells had been found only in aging tissue

The discovery raises the possibility that the start and end of life are intimately connected

The process by which cells cease multiplying is known as senescence. In 1961, biologists Hayflick and Moorehead cryoconserved human fetal cells and found that these divide around 50 times and then simply stop doing so, as occurs in the human body (see recent article, AGING CELLS ARE KEY TO FINDING FOUNTAIN OF YOUTH)

In fact, senescent cells are involved in many of the signs of aging: wrinkled skin, cataracts, and arthritic joints, which are produced by the effect of an increase in these cells. On the contrary, it has been found that by decreasing senescent cells in mice, signs of rejuvenation can be detected in these animals.

Considering that in all research, senescent cells have been found only in old or damaged tissues, the last place one would expect to find them would be at the very beginning of life, in the embryo. Now, however, three scientific teams have reported that they have observed the same phenomenon at this point.

Senescent cells in embryos

For the first time, senescent cells have been found in embryos, and scientists have presented proof that senescence is crucial for their proper development.

This discovery raises the possibility that the start and end of life are intimately connected. In order for life to have a good start, senescent cells are needed, i.e. youth needs a little bit of old age.

Scott Lowe, an expert in senescence at Memorial Sloan-Kettering Cancer Center, who did not participate in the research, has lauded the studies, which point to the unexpected role of old age, and predicted that it would provoke a spirited debate between developmental biologists, who study how embryos are formed.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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In the Journals – June 2017, part two by Aaron Seaman

The first part of the In the Journals post for June 2017 can be found here. And now, for part two…

 

Medical Humanities

SPECIAL ISSUE: Communicating Mental Health

Introduction: historical contexts to communicating mental health

Rebecca Wynter and Leonard Smith

Contemporary discussions around language, stigma and care in mental health, the messages these elements transmit, and the means through which they have been conveyed, have a long and deep lineage. Recognition and exploration of this lineage can inform how we communicate about mental health going forward, as reflected by the 9 papers which make up this special issue. Our introduction provides some framework for the history of communicating mental health over the past 300 years. We will show that there have been diverse ways and means of describing, disseminating and discussing mental health, in relation both to therapeutic practices and between practitioners, patients and the public. Communicating about mental health, we argue, has been informed by the desire for positive change, as much as by developments in reporting, legislation and technology. However, while the modes of communication have developed, the issues involved remain essentially the same. Most practitioners have sought to understand and to innovate, though not always with positive results. Some lost sight of patients as people; patients have felt and have been ignored or silenced by doctors and carers. Money has always talked, for without adequate investment services and care have suffered, contributing to the stigma surrounding mental illness. While it is certainly ‘time to talk’ to improve experiences, it is also time to change the language that underpins cultural attitudes towards mental illness, time to listen to people with mental health issues and, crucially, time to hear.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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The Moral Question That Stanford Asks Its Bioengineering Students

June 28, 2017

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When students in Stanford University’s Introduction to Bioengineering course sit for their final exams, the first question that they have to answer is about our ability to write DNA.

Scientists have fully sequenced the genomes of humans, trees, octopuses, bacteria, and thousands of other species. But it may soon become possible to not just readlarge genomes but also to write them—synthesizing them from scratch. “Imagine a music synthesizer with only four keys,” said Stanford professor Drew Endy to the audience at the Aspen Ideas Festival, which is co-hosted by the Aspen Institute and The Atlantic. Each represents one of the four building blocks of DNA—A, C, G, and T. Press the keys in sequence and you can print out whatever stretch of DNA you like.

In 2010, one group did this for a bacterium with an exceptionally tiny genome, crafting all million or so letters of its DNA and implanting it into a hollow cell. Another team is part-way through writing the more complex genome of baker’s yeast, with 12 million letters. The human genome is 300 times bigger, and as I reported last month, others are trying to build the technology that will allow them to create genomes of this size.

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The Atlantic

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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Huntington’s Disease: Gene Editing Shows Promise in Mouse Studies

My father was a folk song collector, and I grew up listening to the music of Woody Guthrie. On July 14th, folk music enthusiasts will be celebrating the 105th anniversary of Guthrie’s birth in his hometown of Okemah, OK. Besides being renowned for writing “This Land is Your Land” and other folk classics, Guthrie has another more tragic claim to fame: he provided the world with a glimpse at the devastation caused by a rare, inherited neurological disorder called Huntington’s disease.

When Guthrie died from complications of Huntington’s a half-century ago, the disease was untreatable. Sadly, it still is. But years of basic science advances, combined with the promise of innovative gene editing systems such as CRISPR/Cas9, are providing renewed hope that we will someday be able to treat or even cure Huntington’s disease, along with many other inherited disorders.

My own lab was part of a collaboration of seven groups that identified the Huntington’s disease gene back in 1993. Huntington’s disease occurs when a person inherits from one parent a mutant copy of the huntingtin (HTT) gene that contains extra repetitions, or a “stutter,” of three letters (CAG) in DNA’s four-letter code. This stutter leads to production of a misfolded protein that is toxic to the brain’s neurons, triggering a degenerative process that, over time, leads to mood swings, slurred speech, uncontrolled movements, and, eventually, death. In a new study involving a mouse model of Huntington’s disease, researchers were able to stop the production of the abnormal protein by using CRISPR tools to cut the stutter out of the mutant gene.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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Responsibility in the age of precision genomics

by Alexa Woodward

Alexa is a fellow in the Precision Medicine: Ethics, Policy, and Culture project through Columbia University’s Center for the Study of Social Difference. The following is her reflection on the ongoing discussion around the Precision Medicine Initiative that has been the subject of recent political, social, and popular media attention. A recent presentation by Sandra Soo-Jin Lee, PhD, from the Center for Biomedical Ethics at Stanford University spurred our multi-disciplinary discussion of some of the following themes.

What is normal, anyway?

Genetically speaking, that’s precisely the question that the Obama administration’s Precision Medicine Initiative (PMI) seeks to answer. In recruiting and collecting comprehensive genetic, medical, behavioral, and lifestyle data from one million Americans, the scientific and medical communities will be better able to understand what constitutes normal genetic variation within the population, and in turn, what amount of variation causes or contributes to disease or disease risk.[1] Using this data, researchers could potentially create tailored approaches for intervention and treatment of an incredible range of diseases.

The PMI has a secondary aim: to increase the representation of previously underrepresented populations in research – primarily African Americans and Hispanics/Latinos. Inclusion of these groups in research has been a challenge for decades, with lack of access, distrust in the medical and research systems, and institutionalized racism all playing exclusionary roles. More broadly, outside of the government initiative, the promise of precision medicine ultimately seeks to alleviate disparities by finding and addressing supposed genetic differences, and empowering people with information to take responsibility for their health.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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New Concerns Raised Over Value of Genome-Wide Disease Studies

June 21, 2017

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Compare the genomes of enough people with and without a disease, and genetic variants linked to the malady should pop out. So runs the philosophy behind genome-wide association studies (GWAS), which researchers have used for more than a decade to find genetic ties to diseases such as schizophrenia and rheumatoid arthritis. But a provocative analysis now calls the future of that strategy into question — and raises doubts about whether funders should pour more money into these experiments.

GWAS are fast expanding to encompass hundreds of thousands, even millions, of patients (see ‘The genome-wide tide’). But biologists are likely to find that larger studies turn up more and more genetic variants — or ‘hits’ — that have minuscule influences on disease, says Jonathan Pritchard, a geneticist at Stanford University in California. It seems likely, he argues, that common illnesses could be linked by GWAS to hundreds of thousands of DNA variants: potentially, to every single DNA region that happens to be active in a tissue involved in a disease.

In a paper published in Cell on 15 June1, Pritchard and two other geneticists suggest that many GWAS hits have no specific biological relevance to disease and wouldn’t serve as good drug targets. Rather, these ‘peripheral’ variants probably act through complex biochemical regulatory networks to influence the activity of a few ‘core’ genes that are more directly connected to an illness.

… Read More

Image via Flickr Attribution Some rights reserved by The Moonstone Archive

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The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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Precision Oncology: Gene Changes Predict Immunotherapy Response

Caption: Adapted from scanning electron micrograph of cytotoxic T cells (red) attacking a cancer cell (white).
Credits: Rita Elena Serda, Baylor College of Medicine; Jill George, NIH

There’s been tremendous excitement in the cancer community recently about the life-saving potential of immunotherapy. In this treatment strategy, a patient’s own immune system is enlisted to control and, in some cases, even cure the cancer. But despite many dramatic stories of response, immunotherapy doesn’t work for everyone. A major challenge has been figuring out how to identify with greater precision which patients are most likely to benefit from this new approach, and how to use that information to develop strategies to expand immunotherapy’s potential.

A couple of years ago, I wrote about early progress on this front, highlighting a small study in which NIH-funded researchers were able to predict which people with colorectal and other types of cancer would benefit from an immunotherapy drug called pembrolizumab (Keytruda®). The key seemed to be that tumors with defects affecting the “mismatch repair” pathway were more likely to benefit. Mismatch repair is involved in fixing small glitches that occur when DNA is copied during cell division. If a tumor is deficient in mismatch repair, it contains many more DNA mutations than other tumors—and, as it turns out, immunotherapy appears to be most effective against tumors with many mutations.

Now, I’m pleased to report more promising news from that clinical trial of pembrolizumab, which was expanded to include 86 adults with 12 different types of mismatch repair-deficient cancers that had been previously treated with at least one type of standard therapy [1].

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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Even Though Genetic Information Is Available

With the availability of home genetic testing kits from companies such as “23andMe” and “Ancestry DNA,” more people will be getting information about their genetic lineage and what races and ethnicities of the world are included in their DNA

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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Baby Genome Sequencing for Sale in China

June 15, 2017

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A Boston-based DNA sequencing company is offering to decode the complete genomes of newborns in China, leading some to ask how much parents should know about their children’s genes at birth.

Veritas Genetics says the test, ordered by a doctor, will report back on 950 serious early- and later-life disease risks, 200 genes connected to drug reactions, and more than 100 physical traits a child is likely to have.

Called myBabyGenome, the service costs $1,500 and could help identify serious hidden problems in newborns, the company says.

… Read More

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MIT Technology Review

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The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

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Guest Post: Crispr Craze and Crispr Cares

Written by Robert Ranisch, Institute for Ethics and History of Medicine, University of Tuebingen

@RobRanisch

Newly discovered tools for the targeted editing of the genome have been generating talk of a revolution in gene technology for the last five years. The CRISPR/Cas9-method draws most of the attention by enabling a more simple and precise, cheaper and quicker modification of genes in a hitherto unknown measure. Since these so-called molecular scissors can be set to work in just about all organisms, hardly a week goes by without headlines regarding the latest scientific research: Genome editing could keep vegetables looking fresh, eliminate malaria from disease-carrying mosquitoes, replace antibiotics or bring mammoths back to life.

Naturally, the greatest hopes are put into its potential for various medical applications. Despite the media hype, there are no ready-to-use CRISPR gene therapies. However, the first clinical studies are under way in China and have been approved in the USA. Future therapy methods might allow eradicating hereditary illnesses, conquering cancer, or even cure HIV/AIDS. Just this May, results from experiments on mice gave reason to hope for this. In a similar vein, germline intervention is being reconsidered as a realistic option now, although it had long been considered taboo because of how its (side)effects are passed down the generations.

The developmental history of genome editing reveals itself as a recalibration of ethical standards in research. Two years ago, the first-time use of these new tools on (non-viable) embryos in China led to a solid scandal; in retrospect, it is not clear anymore whether the outrage was triggered by ethical concerns or by the circumstance that this (perceived) taboo was broken by China of all countries.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.