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sequencing result - sequencing result (Apr/16/2007 )

purified pcr product which i had given for sequencing was 559 bp.

but bidirectional sequencing results generated from left primers were larger than 559, almost 700.

i dont know reason of this over sequencing if templete is 559 bp.

any one help to solve my confusion.


did you check what the extract sequence data was? Is it nice well define peaks of good sequence or simply random gibberish... tracks of Ns, As and such.

Take a look at the chromas results, the picture that actual sequences results.

If you should us that bit of info, it would greatly help.


I would second pernesblue. If you just look at the sequence infomation (AGCT), then you easily miss the endpoint of your sequence. Depending on the basecaller software, it stops based on an algorithm. Very often you see in the chromas a long sequence of high peaks and suddenly they end, but there stilla lower peaks. That is most often the end of the product, the rest is background. But to be sure, just post some pictures of the chromas.