Rapidly varying DNA sequences in flax

Abstract

The highly repetitive sequences of the flax genome have been characterized. This has been done using a series of cloned probes that represent most, if not all, of the highly repetitive families in the flax genome. All of them are arranged as tandem arrays. The organization and copy number of these sequences has been compared in a number of lines including those lines (termed genotrophs) derived from the flax variety 'Stormont Cirrus' by the environmental induction of heritable changes, two other flax and linseed cultivars, and some of the supposed wild progenitors of flax. It was found that all except the light satellite differed in copy number between some of the lines. A particular subset of the 5S genes was shown to be preferentially affected when changes occurred. The extent of the variation between genotrophs was similar to that between different varieties or between flax and its supposed progenitor.Key words: flax, DNA variation, repeated sequences.