The influence of linkage and inbreeding on patterns of nucleotide sequence diversity at duplicate alcohol dehydrogenase loci in wild barley (Hordeum vulgare ssp. spontaneum)

Jing Zhong Lin, Peter L. Morrell, Michael T. Clegg

Research output: Contribution to journalArticlepeer-review

40 Scopus citations

Abstract

Patterns of nucleotide sequence diversity are analyzed for three duplicate alcohol dehydrogenase loci (adh1-adh3) within a species-wide sample of 25 accessions of wild barley (Hordeum vulgare ssp. spontaneum). The adh1 and adh2 loci are tightly linked (recombination fraction <0.01) while the adh3 locus is inherited independently. Wild barley is predominantly self-fertilizing (∼98%), and as a consequence, effective recombination is restricted by the extreme reduction in heterozygosity. Large reductions in effective recombination, in turn, widen the conditions for linkage to influence nucleotide sequence diversity through the action of selective sweeps or background selection. These considerations would appear to predict (1) homogeneity in patterns of nucleotide sequence diversity, especially between closely linked loci, and (2) extensive linkage disequilibrium relative to random-mating species. In contrast to these expectations, the wild barley data reveal heterogeneity in patterns of nucleotide sequence diversity and levels of linkage disequilibrium that are indistinguishable from those observed at adh1 in maize, an outbreeding grass species.

Original languageEnglish (US)
Pages (from-to)2007-2015
Number of pages9
JournalGenetics
Volume162
Issue number4
StatePublished - Dec 1 2002

Fingerprint

Dive into the research topics of 'The influence of linkage and inbreeding on patterns of nucleotide sequence diversity at duplicate alcohol dehydrogenase loci in wild barley (Hordeum vulgare ssp. spontaneum)'. Together they form a unique fingerprint.

Cite this