BGS 389, Desynapsis 10, des10

Desynapsis p = des,,p (3, 5).
Hordeum vulgare MutL-Homolog 3 = HvMlh3 (1).

Monofactorial recessive (4, 6).
Located in chromosome 5HL (2); des10.p is associated with SNP markers 2_0127 to 12_0259 (positions 189.08 to 203.85 cM) in 5H bins 10 to 11 of the Bowman backcross-derived line BW230 (2). des10.p is between SNP markers 11_11273 (BOPA1_ABC11221-1-3-410 and 11_21203 (BOPA1_7167-466) in BAC contig (contig_38558) (1).

The chromosomes are paired during pachytene and undergo desynapsis during diplotene and diakinesis. The average degree of desynapsis was 2.0, ranging from 7 ring bivalents (d = 0) to 3 ring bivalents plus 2 rod bivalents plus 4 univalents (d = 6). Ovule fertility was 60 to 80% (5). Plants of the Bowman backcross-derived line for des10.p, BW230, were similar to Bowman except that reduced seed set decreased grain yields to about half that of Bowman (3). The des10.p phenotype is the result of a mutation in the mismatch repair gene encoding HvMutL-homolog 3 (HvMlh3) (1). Compared with wild-type, des10 mutants exhibit reduced recombination and fewer chiasmata, resulting in the loss of obligate crossovers and leading to chromosome mis-segregation. Normal synapsis progression was disrupted in des10 mutants, leading to occasional aberrant chromosome segregation at anaphase I, genetically unbalanced tetrads, and a subsequent semi-fertile phenotype (1).

A spontaneous mutant in Betzes (PI 129430) (6).

des10.p (GSHO 601) in Betzes (PI 129430) (4, 6).

des10.p (GSHO 601) in Betzes; des10.p in Bowman*6 (BW230, NGB 22057).

1. Colas, I., M. Macaulay, J.D. Higgins, D. Phillips, A. Barakate, M. Posch, S.J. Armstrong, F.C.H. Franklin, C. Halpin, R. Waugh, and L. Ramsay. 2016. A spontaneous mutation in MutL-Homolog 3 (HvMLH3) affects synapsis and crossover resolution in the barley. New Phytol. 212: 693-707.
2. Druka, A., J. Franckowiak, U. Lundqvist, N. Bonar, J. Alexander, K. Houston, S. Radovic, F. Shahinnia, V. Vendramin, M. Morgante, N. Stein, and R. Waugh. 2011. Genetic dissection of barley morphology and development. Plant Physiol. 155:617-627.
3. Franckowiak, J.D. (Unpublished).
4. Hernandez-Soriano, J.M., and R.T. Ramage. 1973. Coordinator's report: Desynaptic genes. Barley Genet. Newsl. 3:91.
5. Hernandez-Soriano, J.M., and R.T. Ramage. 1974. BGS 389, Normal vs. desynapsis 10, des10. Barley Genet. Newsl. 4:138.
6. Ramage, R.T., and J.M. Hernandez-Soriano. 1972. Desynaptic genes in barley. Barley Genet. Newsl. 2:65-68.

J.M. Hernandez-Soriano and R.T. Ramage. 1974. Barley Genet. Newsl. 4:138.

J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:337.
J.D. Franckowiak. 2011. Barley Genet. Newsl. 41:152.
J.D. Franckowiak. 2018. Barley Genet. Newsl. 48:134-135.