Recently, 9.9 yuan genetic testing advertisements swiped the circle of friends, claiming that it can test which ethnic genes an individual has. With such a low price, people are stunned that the cost of genetic testing has dropped to such a point?
At present, the price of non-invasive prenatal genetic testing, which has become part of the routine prenatal examination process of most expectant mothers, ranges from about 1,000-3,000 yuan, which makes people wonder why the price difference between the two is so big.
An insider in the genetic testing industry told reporters that genetic testing can be divided into two directions in general: one is consumer-based testing for the general public, which is mostly entertainment. The other is for clinical scenarios, which can help doctors determine the cause or carry out precise treatment in terms of genetic diseases, tumors and other diseases.
It is worth noting that, compared with clinical genetic testing, there is no unified industry standard for domestic consumer genetic testing, and there is a lack of relevant supervision, so the scientificity of relevant testing items has been questioned a lot. However, even for clinical genetic testing, there are inevitably many misunderstandings and disputes due to the public's cognitive level and understanding bias.
I did genetic testing, but why did I still give birth to a sick child?
Zhang Xia has always wanted to have a daughter, and her wish finally came true in the summer of 2021. The arrival of lemons brings so much joy to the family. Although it took 11 months to learn to sit and 13 months to crawl, compared with the progress of children of the same age, she didn't think much about it, it may be that each child's flowering period is different, and she must be patient to accompany the child to grow up slowly.
However, the continued developmental delay made her more and more anxious, and she eventually went to the hospital for professional help. Through genetic testing, the child was diagnosed with Rett syndrome, a genetic disorder that severely affects the child's psychomotor development.
She shared her experience on social media, and many people would question whether she didn't do non-invasive prenatal genetic testing during pregnancy, but in fact, she had a series of tests including non-invasive genetic testing before childbirth.
At 13 weeks pregnant, she was screened for Down syndrome and showed an intermediate risk. Because she is an elderly woman, Zhang Xia still chose the latter in the face of the two methods of amniocentesis and non-invasive prenatal genetic testing provided by the doctor.
After the test, Zhang Xia obtained a report showing that there was no abnormality in the baby's chromosome 21 in her belly, and she was already relieved, but she suddenly remembered the doctor's reminder when introducing two testing methods for her: "Non-invasive prenatal testing has a certain residual risk, and the result is no problem and cannot be 100% guaranteed that the child is born normal." ”
In order to be completely reassured, she went for another amniocentesis. "I thought I couldn't gamble with my child's health, so I should try to diagnose it as much as possible. ”
After the amniocentesis was done, the risk of the child being a Down's child was ruled out, and she was relieved to go into labor.
But misfortune eventually befell the family. Like the people who questioned on social media at the beginning, she also couldn't figure it out, they all had prenatal checkups on time, and they also did non-invasive and amniocentesis, shouldn't genetic testing be very accurate, why would the child still be sick?
Non-invasive prenatal genetic testing is only for chromosome testing, and it is a relatively common pair of chromosomes 13, 18, and 21, and Lemon's confirmed Rett syndrome is a monogenic disease, caused by mutations or deletions in the MECP2 gene. She has also been looking forward to the early emergence of a special medicine for this disease.
To dispel misunderstandings, we urgently need to fully understand
Due to the lack of public knowledge about genetic diseases and genetic testing, misunderstandings and disputes occur from time to time. This makes the doctors also very helpless and headaches.
"If you say too little, the pregnant woman will feel that the introduction is not clear, and if you talk too much, the pregnant woman will feel that you are selling, even if all the risks and instructions are synchronized to the pregnant woman in advance, in the end, as long as there is an unfortunate birth defect, there may be a medical dispute. An obstetrics and gynecology expert at a medical institution who did not want to be named said helplessly.
Liao Can, the leader of the prenatal diagnosis department of Guangzhou Women and Children's Medical Center affiliated to Guangzhou Medical University, also said, "At present, the popularity of genetic testing technology is not enough among the people, and the cost is relatively high, and the psychological expectations of people who receive genetic testing are often too high. If there is no comprehensive and correct understanding of the multiple factors of residual risk after a negative test, this will become a trigger for potential disputes in the field of genetic testing. ”。
Zhang Xia's story is a misunderstanding caused by the fact that diseases are not within the scope of product testing, but in addition, due to the diverse types and complex mechanisms of genetically related diseases, especially when encountering rare or complex genetic conditions, it is still impossible to completely avoid the situation that cannot be detected due to the limitations of current detection technology.
"Each technology has advantages and limitations, and the examinee needs to have a comprehensive understanding," said Wu Lingqian, a professor and doctoral supervisor at the School of Life Sciences of Central South University, who has many years of research and clinical experience in the field of prenatal diagnosis. Citing the most commonly tested chromosomal disorders in the prenatal stage as an example, non-invasive prenatal genetic testing is based on the analysis of cell-free fetal DNA in the peripheral blood of pregnant women to assess the risk of related chromosomal diseases. However, this DNA is derived from the placenta, and in rare cases the genetic material of the placenta and the genetic material of the actual fetus may not be exactly the same, so this technique can only be used for screening, not diagnosis. After the high-risk situation is identified, the amniotic fluid of the pregnant woman is further collected for prenatal diagnosis through invasive methods.
It is also important to note that in the event of mosaicism, even if the amniotic fluid is collected for testing, it may be disturbed and the test results may be inaccurate, which is still a problem in the field of prenatal testing.
At the same time, there are still many unknown genetic problems, Liao Can said, "Genetic testing is not perfect, it does not always bring answers, and sometimes it also brings confusion." ”
In her view, genetic testing, as an emerging technology in the medical field, is always in the process of dynamic development and updating, and many results may be unclear or negative at this stage, but with the development and accumulation of technology, there will be changes in the later stage.
"In the field of genetic testing, we must abandon the 'Boxer' mentality, which will feel invulnerable for a while, and then feel that we will be defeated repeatedly. As an ordinary person, in the face of genetic testing, we must learn to recognize it and use it to make it a great weapon for maintaining a healthy body. The chief physician of Huazhong No. 1 Genetic Medicine Center said.
In the eyes of industry insiders, for genetic testing products, it can neither be completely denied because of its existing technical limitations, nor can it be infinitely "deified" because it is an emerging technology, and genetic testing will continue to penetrate into everyone's daily life as a routine health screening and diagnosis and treatment method in the future.
In the face of the current situation, Wu Lingqian reminded that we should do a good job in popularizing science and education in the whole society, and it is unrealistic to detect all problems through one test with current science and technology and medical means. Before the test, the test subject should also be given a detailed description of what the test can solve, and at the same time, no technology can avoid all the remaining risks, and the report interpreter needs to constantly improve his or her own level.
The genetic testing industry is gradually moving towards standardization
With the continuous maturity of testing technology and the continuous expansion of the market, genetic testing companies have sprung up. According to the data of China Business Intelligence Network, there are currently about 16,651 genetic testing-related enterprises in the mainland, according to industry insiders, there are dozens of large-scale laboratories, systematic research and development capabilities, and their own databases, and the industry is inevitably facing uneven professional levels.
At present, the most mature clinical application is the reproductive genetics scenario, and a number of leading companies have been precipitated in the industry, such as BGI, Berry Gene, Boao Biotech, Annoroad and so on. In addition, the field of tumor detection has also developed rapidly in recent years, with huge room for growth, and the leading companies include BGI, Burning Rock Dx, Genetron Health, etc.
In the early stage of industry development, it is inevitable to face some challenges and problems, under the guidance of supervision and policy, driven by the head enterprises of the standard, the industry as a whole is developing in a healthier and more mature direction. It can be expected that these companies will continue to promote technological innovation and expand the scope of services, and are expected to form a more complete industry ecology in the future.
We also see that this industry has huge potential social value and industrial value.
In 2021, the phrase "every small group should not be abandoned" became popular on the Internet, and in the medical insurance negotiations, the "life-saving drug" nusinersen sodium injection for the treatment of the rare disease SMA (spinal muscular atrophy) was reduced from 700,000 yuan to 33,000 yuan per injection, becoming the first high-value rare disease drug to be included in the national medical insurance catalog.
The high cost of R&D and the small number of drug users make the average annual cost of some rare disease treatment drugs as high as millions of yuan, or even millions of yuan. Although in recent years, the scope of the National Medical Insurance Drug List has been appropriately tilted towards special groups such as patients with rare diseases and children. However, relying on the power of medical insurance alone cannot completely solve the heavy burden of rare disease drug treatment on families.
What's even more embarrassing is that many diseases are difficult to diagnose, and even after diagnosis, there is no cure. This is undoubtedly a sudden storm for these families, with both emotional blows and financial burdens.
More broadly, providing long-term medical support and social services to children with birth defects also entails significant pressure and costs on social and public health systems.
80% of rare diseases are hereditary, and most of them are monogenic inherited diseases. Monogenic diseases are caused by mutations in a specific gene, and as long as a person carries this disease-causing gene, he or she may become a carrier and pass it on to his offspring, such as thalassemia, hemophilia and albinism.
In addition to prenatal screening and prenatal diagnosis of fetal hereditary diseases, neonatal/child hereditary disease detection, the application of single-gene carrier screening in the pre-pregnancy stage has made it possible to eliminate many rare diseases from the source. Liao Can said that with the popularization of genetic testing, a large amount of genomic data has been generated, which can help better understand the connection between genomes and diseases, further explore the pathogenesis of genetic diseases and cancer, and then better prevent and treat these diseases, making personalized medicine and precision medicine a reality.
However, as an advanced technology, genetic testing will inevitably go through a process from rejection, acceptance, misunderstanding to popularization in the process of downward landing. After nearly 10 years in China, it is believed that with the advancement of technology and the decline of costs, the pace of genetic testing can go faster.
(Zhang Xia is a pseudonym in this article)
Zheng Chenye/text
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