Vary in length, type, and position. Crucial areas be sequenced? For the simple reason that genome sequencing methods to date only allowed short sequences to be assembled (several hundred or a few thousand bases). Thus, trying to order and make sense of the 200 million bases (remember, highly repetitive and variable) through small fragments was a challenge similar to trying to put together a puzzle in which the pieces are tiny and of the same color. Inesem business school course in research foundations in health sciences more
information long reads reading these dark areas of the genome has been possible thanks to three facts. The first of these is that current sequencing e commerce photo editing service technologies are capable of covering thousands to hundreds of thousands of bases in each read. For the study of the complete genome, the t2t (telomere to telomere) consortium has used two cutting-edge technologies for genome sequencing: the oxford nanopore method , which can read up to a million bases at once (its precision being modest), and the pacbio hifi method , which allows reading about 20,000 letters with almost perfect precision. Secondly, the subsequent exhaustive bioinformatic analysis allows them to be ordered and given meaning.
And third, a special cell line (called chm13) derived from a hydatidiform mole has been used . What is peculiar about this line? That comes from the fertilization of an egg cell without a nucleus, with duplication of the sperm genome. Therefore, they are haploid cells , containing the information of a single genome. Therefore, when analyzing their dna, it is not necessary to identify if the sequence comes from the maternal or paternal pair of chromosomes. In short, the variation is reduced. Much more than new genes the first complete genome ,