ສົມບູນ ມະນຸດ genome sequence of the two X chromosomes and autosomes from the female tissue derived cell line has been completed. This includes the 8% of the genome sequence that was missing in the original draft that was released in 2001.
ສົມບູນ ມະນຸດ genome sequence of the entire 3.055 billion base pairs has been revealed by the Telomere-to-Telomere (T2T) Consortium. This represents the largest improvement to the ມະນຸດ ອ້າງອິງ genome released in 2001 by Celera Genomics and the International ມະນຸດ ກຳ ມະພັນ Sequencing Consortium. That genome sequence covered most of the euchromatic regions while either leaving out the heterochromatin regions or erroneous representation. These regions comprise 8% of the ມະນຸດ genome that has finally been revealed. The new T2T-CHM13 reference1 ປະກອບມີລໍາດັບທີ່ສົມບູນສໍາລັບທັງຫມົດ 22 autosomes ບວກກັບ Chromosome X. ລໍາດັບການອ້າງອີງໃຫມ່ນີ້ຍັງໄດ້ແກ້ໄຂຄວາມຜິດພາດຈໍານວນຫລາຍ, ແລະໄດ້ເພີ່ມປະມານ 200 ລ້ານ bp ຂອງລໍາດັບໃຫມ່ທີ່ມີ 2,226 genes, ໃນນັ້ນ 115 ຄາດວ່າຈະເປັນລະຫັດໂປຣຕີນ.
The current GRCh38.p13 reference genome has been as a result of two major updates, one in 2013 and the other one on 2019 on the 2001 Celera genome sequence. However, it still had 151 million base pairs of unknown sequence distributed throughout the genome, including pericentromeric and sub telomeric regions, duplications, gene and ribosomal DNA (rDNA) arrays, all of which are necessary for fundamental cellular processes. The new reference has been named as T2T-CHM13 as it comes from sequencing the DNA from CHM13 (Complete Hydatiform Mole) cell line and is performed by T2T consortium. The cell line is derived from abnormal fertilized egg or an overgrowth of tissue from the placenta in which women appears to be pregnant (false pregnancy), hence the sequence represents only of the two X chromosomes and autosomes of the female. Multiple sequence technologies have been put to use such as PacBio, Oxford Nanopore, 100X and 70X Illumina sequencers to name a few. The technological advances in sequencing have led to the sequencing of the remaining 8% as mentioned above.
ຂໍ້ຈໍາກັດພຽງແຕ່ຂອງລໍາດັບ T2T-CHM13 ແມ່ນການຂາດໂຄໂມໂຊມ Y. ການຈັດລໍາດັບນີ້ປະຈຸບັນກໍາລັງດໍາເນີນຢູ່, ໂດຍນໍາໃຊ້ DNA ຈາກເສັ້ນຈຸລັງ HG002, ເຊິ່ງມີ 46 (23 ຄູ່) ທີ່ມີ XY karyotype. ຫຼັງຈາກນັ້ນ, ລໍາດັບຈະຖືກປະກອບໂດຍໃຊ້ວິທີການດຽວກັນທີ່ພັດທະນາສໍາລັບ genome CHM13 homozygous.
ຄວາມພ້ອມຂອງ T2T-CHM13 ເປັນການອ້າງອີງໃໝ່ genome ເປັນຕົວແທນຂອງການພັດທະນາທີ່ສໍາຄັນທີ່ຈະຊ່ວຍໃຫ້ເຂົ້າໃຈບົດບາດຂອງພາກພື້ນ heterochromatin ແລະຊ່ວຍເຂົ້າໃຈຜົນກະທົບຂອງມັນຕໍ່ຂະບວນການຂອງເຊນໃນລາຍລະອຽດຫຼາຍກວ່າເກົ່າ. ຈົນກ່ວາການຈັດລໍາດັບ chromosome Y ສໍາເລັດ, ນີ້ຈະເປັນ genome ອ້າງອີງສໍາລັບການສຶກສາໃນອະນາຄົດໃນການເຂົ້າໃຈຂະບວນການແລະຫນ້າທີ່ຂອງເຊນ.
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ເອກະສານ
- Nurk S, Koren S, Rhie A, Rautiainen M, Bzikadze A V, Mikheenko A et al. The complete sequence of a ມະນຸດ genome bioRxiv 2021.05.26.445798; DOI: https://doi.org/10.1101/2021.05.26.445798
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