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| Fig. 1 |
The sequences in public databases, e.g. Genbank, are not showing Chargaff ratios in dsDNA.
They are modern sequences from the work of the well known "International Human Genome Sequencing Consortium".
See Nature 431 (7011), 931-945 (2004).
In the previous two posts of this series ancient human DNA sequences were analyzed (What Happened to Chargaff's Rules?, 2).
Today we analyze genes in 614 sequences of modern human genetic sequences (Appendix 1, 2, 3, 4, 5, 6, 7, 8).
These modern DNA sequences likewise do not match Chargaff Rules.
I modified the appendices by removing the atom counts tables for easier viewing, and made sure that the FASTA version will load when you select "Link GenBnk".
Anyway, the way to determine if the sequence is "at odds" with Chagraff's Rule is to use simple arithmetic to count the number of 'A' nucleotides in the sequence and to count the 'T' nucleotidses in the same sequence to see if they match.
Next, do the same thing with 'C' nucleotides to see if they have the same count as the 'G' nucleotides.
My software did the count and constructed an HTML table for each of the 614 modern human sequences.
Chargaff's Rule says the numbers must match if the sequence is accurate.
See the short video below by Assistant Chair of the Science Department and Director of Stan-X (Stanford) Partnerships of The Lawrenceville School.
The previous post in this series is here.
