During sequencing of PCR products very often a so-called TAMRA blob
appears at approx. 180-200 bases. On the gel image you can see it as a
yellow haze. It obscures 6 to 10 bases. Very inconvenient. Does anybody
else experience such blobs ? It seems to be independent of the template
sequence, but dependent on the size of the PCR product. Shorter PCR
product get the blob somewhat earlier.