<p style="text-align: justify;"><b>The Introduced DNA</b></p>

<p style="text-align: justify;">Southern blot analysis of genomic DNA from transgenic potato lines BT6, BT12, BT17, BT18, and BT23 indicated that single copies of T-DNA were integrated at a single insertion site. Analysis of B10 indicated that two copies of the <i>cry3A</i> gene were inserted in tandem while BT16 contained two copies inserted at separate genetic loci. The data provided showed that there was no incorporation of any coding region from outside the T-DNA borders.</p>

<p style="text-align: justify;"><b>Genetic Stability of the Introduced Trait</b></p>

<p style="text-align: justify;">The stable inheritance of the novel traits in potato lines BT6, BT10, BT12, BT16, BT17, BT18, and BT23 was demonstrated over four generations of vegetative propagation.</p>

<p style="text-align: justify;"><b>Expressed Material</b></p>

<p style="text-align: justify;">In <i>B. thuringiensis</i>, expression of the <i>cry3A</i> gene results in the production of two proteins, a full length 73 kDa (644 amino acids) Cry3A protein and a smaller molecular weight species (68 kDa; 597 amino acids) resulting from inframe translation initiation at an internal ATG sequence. This latter protein, referred to as Cry3A band 3 protein, lacks 48 amino acids from the N-terminus but retains insecticidal activity, and corresponds to the form of the protein expressed in these transgenic potatoes.</p>

<p style="text-align: justify;">Western immunoblot analysis of protein extracts from transgenic potato tissue demonstrated the presence of a 68 kDa immunoreactive species as well as a smaller molecular weight species of 55 kDa. Studies were conducted to confirm that the 68 kDa protein product of the <i>cry3A</i> gene transferred into potato plants undergoes processing or degradation in the plant cell into a smaller protein of 55 kDa. The two protein products seen in the plant cell appear identical to that observed in commercial B.t.t preparations.</p>

<p style="text-align: justify;">Expression of the B.t.t. protein Cry3A protein was quantified for the seven lines and found to average from 14.4 to 19.1 &micro;g/g (f.w.) of leaf tissue and 0.8 &micro;g/g (f.w.) of tuber tissue, corresponding to 0.09 to 0.12% of total foliage protein and 0.004% of total tuber protein. The mean whole plant expression for all seven lines was 6.64 &micro;g/g (f.w.) of tissue, corresponding to 0.04% of the total plant protein.</p>

<p style="text-align: justify;">Expression of NPTII was estimated to average 0.339 &micro;g/g (f.w.) of leaf tissue, and 0.197 &micro;g/g (f.w.) of tuber tissue, corresponding to 0.002% of foliage protein and 0.001% of tuber protein.</p>
