Editing Genes Shouldn’t be too Scary – Unless They Are the Ones that Get Passed to Future Generations

Eleanor Feingold wrote . . . . . . . . .

Gene editing is one of the scarier things in the science news, but not all gene editing is the same. It matters whether researchers edit “somatic” cells or “germline” cells.

Germline cells are the ones that propogate into an entire organism – either cells that make sperm and eggs (known as germ cells), or the cells in an early embryo that will later differentiate into different functions. What’s critical about those particular cells is that a change or mutation in one will go on to affect every cell in the body of a baby that grows from them. That’s why scientists are calling for a moratorium on editing the genes of germ cells or germline cells.

Somatic cells are everything else – cells in particular organs or tissues that perform a specific function. Skin cells, liver cells, eye cells and heart cells are all somatic. Changes in somatic cells are much less significant than changes in germline cells. If you get a mutation in a liver cell, you may end up with more mutant liver cells as the mutated cell divides and grows, but it will never affect your kidney or your brain.

Our bodies accumulate mutations in somatic tissues throughout our lives. Most of the time humans never know it or suffer any harm. The exception is when one of those somatic mutations grows out of control leading to cancer.

I am a geneticist who studies the genetic and environmental causes of a number of different disorders, from birth defects – cleft lip and palate – to diseases of old age like Alzheimer’s. Studying the genome always entails thinking about how the knowledge you generate will be used, and whether those likely uses are ethical. So geneticists have been following the gene editing news with great interest and concern.

In gene editing, it matters enormously whether you are messing with a germline cell, and thus an entire future human being and all its future descendants, or just one particular organ. Gene therapy – fixing faulty genes in individual organs – has been one of the great hopes of medical science for decades. There have been a few successes, but more failures. Gene editing may make gene therapy more effective, potentially curing important diseases in adults. The National Institutes of Health runs a well-respected and highly ethical research program to develop tools for safe and effective gene editing to cure disease.

But editing germline cells and creating babies whose genes have been manipulated is a very different story, with multiple ethical issues. The first set of concerns is medical – at this point society doesn’t know anything about the safety. “Fixing” the cells in the liver of someone who might otherwise die of liver disease is one thing, but “fixing” all of the cells in a baby who is otherwise healthy is a much higher-risk proposition. This is why the recent announcement that a Chinese scientist had done just that created such an uproar.

But even if we knew the procedure was safe, gene editing of the germline would still catapult us straight into all of the “designer baby” controversies and the problems of creating a world where people try to micromanage their offspring’s genes. It does not take much imagination to fear that gene editing will could bring us a new era of eugenics and discrimination.

Does gene editing still sound scary? It should. But it makes a big difference whether you are manipulating individual organs or whole human beings.

Source: The Conversation

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Golden Canapes

Ingredients

1/2 cup light mayonnaise
3 tbsp chives, chopped
1 tsp Dijon mustard
1/4 – 1/2 tsp red chili flakes
6 hard-cooked eggs, chopped
1/2 cup shredded Cheddar cheese
1/4 cup toasted, roughly chopped pecans
24 slices multi-grain baguette

Method

  1. Preheat broiler oven.
  2. In a medium bowl, stir together mayonnaise, chives, mustard and chili flakes until well blended.
  3. Gently stir in eggs, cheese and pecans.
  4. Dollop each bread slice with 1 rounded tablespoon of the egg mixture.
  5. Broil about 6 inches from heat until lightly browned and bubbly, about 1 to 2 minutes. Serve immediately

Makes 24 pieces.

Source: Manitoba Egg Farmers

In Pictures: Home-made Sandwiches

2019 Shopper’s Guide to Pesticides in Produce Released by the Environmental Working Group

See large image . . . . .

See large image . . . . .

Source: Environmental Working Group

Kale Joins the Ranks of the Annual ‘Dirty Dozen’ Pesticide List

Denise Powell wrote . . . . . . . . .

Kale, that popular green of the health conscious, has joined the ignoble list of 12 fruits and vegetables with the most pesticide residues, according to the Environmental Working Group. The last time kale was on the list was in 2009 when it was ranked eighth. Strawberries and spinach took the top two spots again this year, respectively, followed by kale.

Since 2004, the group — a nonprofit, nonpartisan environmental organization — has annually ranked pesticide contamination in popular fruits and vegetables for its Shopper’s Guide, noting those with the highest and lowest concentration of pesticides after being washed or peeled. Pesticides include an array of chemicals that kill unwanted insects, plants, molds and rodents. These chemicals keep pests from destroying produce but also expose humans to residues through their diet. This guide shares the results of the 47 tested fruits and vegetables, so consumers can buy foods with lower amounts of pesticides.

The “Dirty Dozen” and “Clean Fifteen,” a list of the top 15 tested produce contaminated with the least amounts of pesticide, are based off more than 40,900 fruit and vegetable samples tested by the Food and Drug Administration and the United States Department of Agriculture. The types and amounts of pesticides used vary based upon pests and weather, according to EWG.

Analysis of recent data showed that 70% of this produce sold for consumption contained pesticide residues.

How do pesticides impact health?

While pesticides are used to protect growing fruits and vegetables, they can also endanger humans, per the World Health Organization. Human consumption of pesticides has been shown by studies to be associated with cancer risk, fertility and other health concerns. EWG research analyst Carla Burns explained in statement, “The main route of pesticide exposure for most Americans who do not live or work on or near farms is through their diet.” By helping consumers know what foods to be more health-conscious about or to gravitate toward in the grocery store, this guide intends to assist making decisions about the way pesticide regulation impacts health.

Fear shouldn’t be a part of the decision whether to buy foods on the pesticide list, said Teresa Thorne, executive director of the Alliance for Food and Farming, a non-profit that represents organic and conventional farmers of fruits and vegetables.

Thorne noted a past study in the Journal of Toxicology that was critical of EWG’s Dirty Dozen list, and found that eating organic produce didn’t decrease consumer risk. “That’s largely because residues are so low, if present at all,” she said.

Research on the effects of pesticides on humans is ongoing, and there is not a complete understanding of whether there is a particular amount of pesticides considered to be safe. The American Academy of Pediatrics acknowledges there are reasons to be concerned about the exposure of developing children to pesticides, especially before birth. Concerns include effects on development and behavior.

What produce has high amounts of pesticides on the list?

In order of pesticide concentration, 2019’s Dirty Dozen list is: strawberries, spinach, kale, nectarines, apples, grapes, peaches, cherries, pears, tomatoes, celery and potatoes. Among these, kale and spinach contained 1.1 to 1.8 times more pesticide residue in weight than other batches of produce. This list varies, as does pesticide use in agriculture. “The types and amount of pesticides a grower uses is going to depend upon the pests that the grower is dealing with and the weather. Wetter weather will often increase the use of fungicides,” says Chris Campbell, EWG’s vice president for information technology.

Despite the high pesticide residues of spinach and kale, strawberries have maintained their place at the top of the Dirty Dozen list. Strawberries are popular — Americans eat an estimated 8 pounds per year — but the chemicals used to protect and preserve strawberries raise concern and some have been banned by the European Union. The fruit gained its notorious status because of the United States Department of Agriculture concluding strawberries are most likely, among the tested produce, to retain pesticide residues even after being picked and washed.

What is so surprising about kale being number three on the Dirty Dozen list?

Kale is known for being a source of vitamins and other nutrients, but the vegetable could also be tainted by cancer-causing pesticides. The report’s results showed that 92% of the samples of conventionally grown kale were positive for two or more pesticide residues, and a single sample of kale sometimes contained as many as 18 different pesticide residues. The most common pesticide detected was Dacthal, also known as DCPA, and has been identified as a potential cancer-causing agent. Europe has prohibited its use since 2009.

What produce has low amounts of pesticides?

Produce that are among the top of the list for reducing the exposure of consumers to pesticides include avocados, sweet corn, pineapples, frozen sweet peas and onions. In contrast to the Dirty Dozen, there was no detection of pesticide residues in 70% of these foods. Less than 1% of avocados and sweet corn tested positive for pesticides and were considered the cleanest of the list.

How can you avoid pesticides?

The recommendations from the Environmental Working Group are to buy and eat organic produce, especially fruits and vegetables found on the Dirty Dozen list. However, if your budget does not allow you to eat organic, fruits and vegetables are better than none.

“The science shows that what people need to know is to eat more fruits and vegetables every day, conventional or organic, choose either. No list needed,” said Thorne of the Alliance for Food and Farming.

Source: CNN