My colleagues and I had a disscusion about this case. They say, that this peak is not countable as an allele. The problem is that it is present in majority of an individuals, which are polyploid. Should I ignore this peak or count as real allele?
It's difficult to say with only looking at one sample but it does look like it could be a "real" allele. Have you tried re-amping a subset of samples to see if the peak consistently amps? You could also try running some analyses, with and without scoring that peak to see if your results change.