Why are there such high levels of genetic uncertainty

On July 14, huayong gene was listed on the shenzhen stock exchange and won a lot of attention, even leading to the continuous rise of the precision medical concept stock, and the whole genetic industry started another hurricane.

But is the genetic industry really such a miracle?

In a harvard speech this year, Facebook's chief executive also referred to the elimination of diseases by modifying genes.

Is this all possible?

The average person can't interpret the result of the test themselves, the professional worker's responsibility is as heavy as mount tai.

In a recent article in the Atlantic, a few American cases have uncovered huge problems with genetic sequencing.

Genetics can bring more accuracy, more comprehensive diagnosis and individualized treatment to medicine, but for some people, genetic testing has given them more questions.

AnneMarie Ciccarella, a 57-year-old brunette, speaks quickly and with a clear New York accent.

She thought she knew everything about breast cancer.

In 1987, her mother was diagnosed with breast cancer, and several of her other family members suffered from the disease.

When the doctor found suspicious lumps in one of her breasts, she immediately sought help for genetic testing to find two BRCA mutations.

One of the mutations, more than 20 percent, may be related to the family inheritance of breast cancer.

Ciccarella thought the test results would give her an explanation.

On the contrary, the detection only identified unknown variation in BRCA1 and BRCA2 (VUS, leifeng net: a variation of a disease associated with disease).

Unlike the mutations that cause disease and benign tumors, the understanding of these genetic variations is not enough to indicate whether they are related to disease.

"I only know that people's genes mutate, and the cancer cases in my family have led me to believe that I have mutations in my genes.

I don't know that there are so many unknown situations, I don't get the conclusion, I smoke so much blood, the feedback is a big question mark."

Ciccarella said.

Thousands of people have tested their BRCA genes to determine whether they are genetically more likely to develop breast cancer, ovarian cancer, prostate cancer and other cancers.

About 5 percent of people found that their genes carry unknown mutations.

The unknown mutation rate is much higher than other types of mutations: one study showed that nearly 20 percent of all genetic tests carried unknown mutations.

Genetic mutations that cause disease are rare, but that does not mean that all rare mutations can cause disease.

So should we change the way we deal with genetic testing uncertainty?

"There's a lot of uncertainty here," said Robert Klitzman, a bioethicist at Columbia University in New York.

People want genetic testing to be like a pregnancy test, he explained. "pregnancy test results will tell you if you're really pregnant.

But genetic testing, on the other hand, is more like a weather report.

And most people are unprepared to face this uncertainty.

When the scientists set a year ago for the BRCA gene detection of women in the process of the investigation found that uncertainty results of women than those who had a clear results (even if the results show that the pathogenic) women more tension and anxiety.

A follow-up study has shown that people who believe they have a higher risk of illness are less tolerant of uncertain outcomes and are more likely to suffer long-term psychological stress.

Long before her sequencing results, Ciccarella's family history made her decide to have a bilateral mastectomy.

For her, the question of whether she would have breast cancer had been answered, and had been prepared for the worst.

But for her own children, she still hopes to be prompted to know if they have the genetic risk of cancer.

But, like many families, they find that genetic sequencing does not provide a clear answer to everyone.

• Unexplained genetic mutation

We are all mutants.

A long time ago, we became our 3 billion DNA fragments, like the words carved on a monument, only to change in small ways.

Scientists used to think that mutations in DNA were largely harmful.

It wasn't until the end of the 20th century and the early 21st century, when humans first sequenced their genomes, that researchers realized they were wrong about mutations.

Genetic mutations are not uncommon and damaging to health. He is widely dispersed in the human genome.

The average person carries around 400 unique mutations, but most of us don't suffer from it.

That challenges some of the basic principles of genetics, as well as the way scientists and doctors explain genetic testing.

When Robert Resta, a genetic consultant at the Swedish medical center, began studying genetic tests in the late 1980s, he could only identify abnormal chromosomal abnormalities or mutations in large amounts of DNA.

When other types of genetic testing are introduced, such as the method used to detect CFTR gene mutations that lead to cystic fibrosis, the related explanations are still simple and straightforward.

Because most people who accepted the CFTR gene sequencing have clinical symptoms of cystic fibrosis, so naturally, Resta believe, observed on the gene mutations are the cause of cystic fibrosis.

In the past few years, however, the cost of gene sequencing has fallen sharply, and doctors are increasingly inclined to require DNA testing early in the diagnosis.

As more data is collected, the mutations we carry are increasingly revealed.

"It turns out that mutations are the norm.

It is normal to find mutations in genes.

It's a whole new way of thinking about the human genome.

If you don't find a mutation, it's possible that your sequencer may have problems, "says Resta.

Stanford university's center for hereditary cardiovascular disease genetic counselors Colleen Caleshu said, when scientists through the large number of genes in a single inspection is the genome, almost say, at least they will find an unknown variable.

She added: "the more genes you detect, the more mutations you find.

"There are many mutations in our genes, and most mutations are very rare, but the rarity means it is unexplainable."

All in all, we know too little about what we're testing.

The second generation of gene sequencing technology has made genetic testing popular to look for a range of genetic mutations that might be associated with patient symptoms.

But at the same time, the uncertain grey area is expanding.

Of the three possible outcomes, Resta said, the risk of illness, benign or uncertain, was the least likely, but the probability of uncertainty was highest.

If clinicians are unable to explain the results of genetic tests, it is also difficult for patients to accept.

Yvonne Bombard, who spent the last years of her career as a genomic health service researcher at st. Michael's Hospital in Toronto, aims to understand how families understand genetic testing results.

"There is very little research on the impact of uncertain outcomes on families," says Bombard.

A small study of psychological oncology looked at 24 women with breast or ovarian cancer who were diagnosed with unknown mutations in genetic tests.

Studies have found that many of them misunderstand the results.

Although two-thirds of people still clearly remember in three years later, their detection is mutation detected in the unclassified, but 79% of the people understand the results as a higher genetic risk of developing breast cancer.

And a third of people have made major changes to their health care plans based on the results, which are not recommended by Resta and Caleshu.

Families with suspected genetic disorders face similar difficulties.

Parents tend to interpret what is not "benign" as a reason for their child's illness, explains Caleshu.

But she also understood that after all these families had been looking for so long, they wanted an answer.

These families may be disappointed in the health care establishment, and when patients misinterpret the diagnosis, they are unconcerned and hung up.

Without a clear description, it is easy to assume that the genetic variation found in tests must be harmful.

The main job of Caleshu is to provide pre-inspection counseling so that patients can understand the risks and limitations of testing.

She says her team has switched to a way to communicate the results of tests, so that patients and doctors don't focus too much on unknown mutations.

Yet even with the right genetic guidance, uncertainty can still be unsettling.

Opinions vary, causing confusion among the patients' families

Ciccarella has seen her mother suffer from chemotherapy, and she has experienced similar hardships.

If she could get the genetic information that would help her future generations avoid the pain through screening, family planning, and preventive mastectomy, she would do it.

She decided to let another agency check her genetic test results and asked Myriad Genetics, the sequencing company, to give her data.

But Myriad's declined.

Because they have patents on these genetic data, no other person or institution can share their proprietary genetic data.

So she began to pay attention to the ACLU's lawsuit against Myriad's genetic patents.

Hopefully, if they win, she might get another answer at another agency.

In 2013, the U.S. Supreme Court upheld the ACLU, and Myriad's patents expired.

But Myriad still refuses to release the original sequencing data, saying it would violate health privacy laws.

Ciccarella teamed up with ACLU and three other people who wanted to get their complete sequence data to Sue Myriad in 2016, arguing that HIPAA was a way to support patients with their own data.

On May 18, the day before the lawsuit, Myriad reversed its position and released sequence data to Ciccarella.

She found the Myriad will one unknown variable reclassified as benign, but when she

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