ການສຶກສາສະແດງໃຫ້ເຫັນຄໍາສັນຍາສໍາລັບການປິ່ນປົວພະຍາດທາງພັນທຸກໍາໃນສັດລ້ຽງລູກດ້ວຍນົມໃນລະຫວ່າງການພັດທະນາຂອງ fetal ໃນສາມເດືອນທໍາອິດຂອງການຖືພາ
A genetic ຄວາມຜິດປົກກະຕິແມ່ນເງື່ອນໄຂຫຼືພະຍາດທີ່ເກີດຈາກການປ່ຽນແປງທີ່ຜິດປົກກະຕິຫຼືການກາຍພັນໃນ DNA ຂອງບຸກຄົນໃນ gene. ຂອງພວກເຮົາ DNA provides the required code for making proteins which then perform most of the functions in our body. Even if one section of our DNA gets altered in some way, the protein associated with it can no longer carry out its normal function. Depending upon where this change happens either it can have a little or no effect or it might alter the cells so much that it could then lead to a genetic disorder or illness. Such changes are caused by errors in DNA replication (duplication) during growth, or environmental factors, lifestyle, smoking and exposure to radiation. Such disorders are passed on to the offspring and start to occur when the baby is developing in mother’s uterus and are therefore referred to as ‘birth defects’.
Birth defects can be minor or extremely severe and may affect appearance, function of an organ and some aspect of physical or mental development. Millions of children are born annually with serious genetic conditions. These defects can be detected during pregnancy as they are evident within the first three months of pregnancy when the organs are still forming. A technique called amniocentesis is available for detecting genetic abnormalities in the foetus by testing amniotic fluid extracted from the uterus. However, even with amniocentesis, treating them is not possible as no options are available to make any corrections before birth of the baby. Some of the defects are harmless and require no intervention but some others can be of serious nature and may require long-term treatment or even be fatal for the infant. Some defects can be corrected shortly after birth of the baby – example within a week’s time – but mostly it is too late for treatment.
ການປິ່ນປົວ genetic condition in an unborn baby
For the first time the revolutionary gene editing technique has been used to cure a ‘genetic disorder’ in mice during foetal development in the uterus in a study by researchers at Carnegie Mellon University and Yale University. It is well established that during early development in the embryo (during first three months of a pregnancy) there are many stem cells (an undifferentiated cell type which can become any type of cell upon maturation) that are dividing at a fast rate. This is the pertinent time point where a genetic mutation if corrected would reduce the impact of the mutation on embryo-to-foetal development. There are chances that a severe genetic condition could even be cured and the baby is born without the unintended birth defects.
ໃນການສຶກສານີ້ຈັດພີມມາຢູ່ໃນ ການສື່ສານທໍາມະຊາດ researchers have used a peptide nucleic acid-based gene editing technique. This technique has been used before to treat beta thalassemia – a genetic blood disorder in which haemoglobin (HB) produced in the blood is reduced considerably which then affects normal oxygen supply to various parts of the body leading to severe abnormal consequences. In this technique, unique synthetic molecules called peptide nucleic acids (PNAs) (made of a combination of synthetic protein backbone with DNA and RNA) were created. A nanoparticle was then used to transport these PNA molecules along with “healthy and normal” donor DNA to the location of a genetic mutation. The complex of PNA and DNA identifies the designated mutation at a site, PNA molecule then binds and unzips the double helix of mutated or faulty DNA. Lastly, donor DNA binds with the mutated DNA and automates a mechanism to correct the DNA error. The main significance of this study is that it was done in a foetus, thus researchers had to use a method analogous to amniocentesis wherein they inserted the PNA complex into the amniotic sac (amniotic fluid) of pregnant mice whose foetuses were carrying the gene ການກາຍພັນທີ່ເຮັດໃຫ້ເກີດ beta thalassemia. ຫຼັງຈາກການສັກຢາ PNA ຫນຶ່ງ, 6 ເປີເຊັນຂອງການກາຍພັນໄດ້ຖືກແກ້ໄຂ. ຫນູເຫຼົ່ານີ້ສະແດງໃຫ້ເຫັນການປັບປຸງອາການຂອງພະຍາດເຊັ່ນ: ລະດັບຂອງ hemoglobin ຢູ່ໃນລະດັບປົກກະຕິເຊິ່ງສາມາດຕີຄວາມຫມາຍໄດ້ວ່າຫນູໄດ້ຮັບການ 'ປິ່ນປົວ' ຂອງສະພາບ. ພວກເຂົາເຈົ້າຍັງໄດ້ສະແດງໃຫ້ເຫັນອັດຕາການລອດຕາຍເພີ່ມຂຶ້ນ. ການສັກຢານີ້ແມ່ນຢູ່ໃນຂອບເຂດຈໍາກັດຫຼາຍ, ແຕ່ນັກຄົ້ນຄວ້າຫວັງວ່າອັດຕາຜົນສໍາເລັດທີ່ສູງຂຶ້ນສາມາດບັນລຸໄດ້ຖ້າຫາກວ່າການສັກຢາໄດ້ຖືກເຮັດຫຼາຍຄັ້ງ.
ການສຶກສາແມ່ນມີຄວາມກ່ຽວຂ້ອງເພາະວ່າບໍ່ໄດ້ສັງເກດເຫັນເປົ້າຫມາຍນອກແລະພຽງແຕ່ DNA ທີ່ຕ້ອງການເທົ່ານັ້ນທີ່ຖືກແກ້ໄຂ. ເຕັກນິກການດັດແກ້ພັນທຸກໍາເຊັ່ນ CRISPR / Cas9 ແມ່ນໃຊ້ງ່າຍກວ່າເພື່ອຈຸດປະສົງການຄົ້ນຄວ້າ, ມັນຍັງເປັນຂໍ້ໂຕ້ແຍ້ງເພາະວ່າມັນຕັດ DNA ແລະປະຕິບັດຂໍ້ຜິດພາດນອກສະຖານທີ່ຍ້ອນວ່າພວກມັນທໍາລາຍ DNA ປົກກະຕິນອກເປົ້າຫມາຍເຊັ່ນກັນ. ເນື່ອງຈາກຂໍ້ຈໍາກັດນີ້ພວກເຂົາບໍ່ເຫມາະສົມທີ່ສຸດສໍາລັບການອອກແບບການປິ່ນປົວ. ພິຈາລະນາປັດໄຈນີ້, ວິທີການທີ່ສະແດງໃຫ້ເຫັນໃນການສຶກສາໃນປະຈຸບັນພຽງແຕ່ຜູກມັດກັບ DNA ເປົ້າຫມາຍແລະການສ້ອມແປງແລະສະແດງຂໍ້ຜິດພາດນອກສະຖານທີ່. ຄຸນນະພາບເປົ້າຫມາຍນີ້ເຮັດໃຫ້ມັນເຫມາະສົມສໍາລັບການປິ່ນປົວ. ວິທີການດັ່ງກ່າວໃນການອອກແບບໃນປະຈຸບັນຂອງມັນຍັງສາມາດຖືກນໍາໃຊ້ເພື່ອ 'ປິ່ນປົວ' ເງື່ອນໄຂອື່ນໆໃນອະນາຄົດ.
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{ທ່ານສາມາດອ່ານເອກະສານການຄົ້ນຄວ້າຕົ້ນສະບັບໄດ້ໂດຍການຄລິກທີ່ລິ້ງ DOI ທີ່ໃຫ້ໄວ້ຂ້າງລຸ່ມນີ້ໃນລາຍຊື່ແຫຼ່ງທີ່ອ້າງອີງ}
ແຫຼ່ງຂໍ້ມູນ (s)
Ricciardi AS et al. 2018. ໃນການຈັດສົ່ງ utero nanoparticle ສໍາລັບການແກ້ໄຂ genome ສະເພາະເວັບໄຊທ໌. ການສື່ສານທໍາມະຊາດ. https://doi.org/10.1038/s41467-018-04894-2
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