Figure 3. The behaviour of the chromosome 3H^ch homologues (labelled by genomic in situ hybridisation) during metaphase I.

(a) In the line carrying the version of chromosome 3H^ch in which a deletion on the long arm has removed neither the long arm telomere nor the subtelomeric region, the homologues form a ring bivalent (see inset), reflecting chiasma formation on both arms.(b) In the line carrying the version of chromosome 3H^ch in which a deletion on the short arm has removed the subtelomeric region, a rod bivalent forms, reflecting the lack of chiasma formation on the short arm (arrowed). Scale bar 10 µm.