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DNA molecular weight = nA*251.24 + nT*242.23 + nC*227.22 + nG*267.24 + (n-1)*61.97 RNA molecular weight = nA*267.24 + nU*244.20 + nC*243.22 + nG*283.24 + (n-1)*61.97 |
Here "nA", "nT", "nC", "nG", "nU" denote the number of the corresponding nucleotide in the molecule, "n" is the number of all bases (61.97 is the weight of an internal phosphate).
Note that for degenerate base characters average value of nucleotide weight is used, for example, if the sequence also contain "Y" characters (that is "C" or "T"), the sum will include one more summand - "nY*(242.23 + 227.22)/2".
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