Nerd Alert!
I'm one of those people who can't make sense out of something unless I go over it from first principle.
I know its simple, but I didnt "get" the algorithm for calculating AA position from DNA seq position till I worked it out myself.
As a review: Every AA (Amino Acid) is coded for by a sequence of 3 DNA bases. So each codon (group of 3 DNA bases (letters)) has 3 positions.
Ok, here's the algorithm:
1. Take the DNA letter position of the mutant base and divide by 3.
2. You will get either a whole number, a number.3333 or a number.666666.
3. If a whole number, then the AA mutated is that number, position 3
4. Else, If its a number.33333 then the AA mutated is that number +1, position 1.
5. Else, If its a number.66666 then the AA mutated is that number +1, position 2.
Examples:
Q: DNA position 516 in a gene is mutated, whats the amino acid number and the codon position that is mutated?
Answer: 516/3 = 172 Its a whole #, so its AA 172, position 3.
Q: DNA position 661 in the same gene is also mutated. What amino acid number and codon position is this?
Answer: 661/3 = 220.33333. Because its .33333, then its amino acid 221, position 1.
Q. DNA position 1145 is mutated. What amino acid number and codon position is mutated?
Answer: 1145/3 = 381.66667. Its 382, position 2.
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Ok, I r ready to teach bioinformatics for dummies yes?
I know its simple, but I didnt "get" the algorithm for calculating AA position from DNA seq position till I worked it out myself.
As a review: Every AA (Amino Acid) is coded for by a sequence of 3 DNA bases. So each codon (group of 3 DNA bases (letters)) has 3 positions.
Ok, here's the algorithm:
1. Take the DNA letter position of the mutant base and divide by 3.
2. You will get either a whole number, a number.3333 or a number.666666.
3. If a whole number, then the AA mutated is that number, position 3
4. Else, If its a number.33333 then the AA mutated is that number +1, position 1.
5. Else, If its a number.66666 then the AA mutated is that number +1, position 2.
Examples:
Q: DNA position 516 in a gene is mutated, whats the amino acid number and the codon position that is mutated?
Answer: 516/3 = 172 Its a whole #, so its AA 172, position 3.
Q: DNA position 661 in the same gene is also mutated. What amino acid number and codon position is this?
Answer: 661/3 = 220.33333. Because its .33333, then its amino acid 221, position 1.
Q. DNA position 1145 is mutated. What amino acid number and codon position is mutated?
Answer: 1145/3 = 381.66667. Its 382, position 2.
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Ok, I r ready to teach bioinformatics for dummies yes?