One positive clone, pcSmY1.4, was isolated and used to probe genomic Southern blots.

Three positive clones were also obtained from a M. eugenii genomic library.

For each probe find all neighbouring probes, ie probes linked by jointly positive clones.

Three positive clones were obtained from 250,000 plaques.

Plasmid DNA of 8-10 different positive recombinant clones was isolated and sequenced.

Colony blots were performed and positive clones were selected for further study.

Two types of positive overlapping clones (18A and REP 2 -2.7) were isolated.

All positive clones were confirmed by PCR with appropriate primer pairs.

One positive clone (R961) was identified and DNA was purified.

Southern blotting was used to identify positive clones which were then sequenced to provide direct evidence for the existence of the new isoform.