Genetic mapping of oligogenic traits using maximum likelihood functions - backcrossing populations

Rodrigo Barros ROCHA[1]

Júpiter Israel MURO-ABAD[2]

Cosme Damião CRUZ[3]

Willian Silva BARROS[4]

Everaldo Gonçalves BARROS3

Elza Fernandes de ARAÚJO[5]

§    ABSTRACT: The qualitative nature and epistatic interaction underlying the oligogenic inheritance pattern should not be interpreted by traditional methods for QTL (Quantitative Trait Loci) detection. The objective of this study is to propose an alternative method for oligogenic loci detection– OTL (Oligogenic Trait Loci). In the Oligogenic Trait Mapping Method (O.T.M.M.), maximum likelihood probability functions were used to obtain “r” estimates, that express the distance among the molecular markers and the OTL loci, adjusted to the data using conditional probabilities of occurrence of the molecular markers and the OTL loci. Results show that the method was adequate for OTL detection even in relatively small backcrossing populations. Comparative analysis showed that the “r” O.T.M.M. estimates were more accurate than the single marker and simple interval mapping estimates. The O.T.M.M. does not need previous information on marker order in the linkage groups and is not affected by the presence of more than one QTL in a same linkage group.

§    KEYWORDS: Genetic mapping; Q.T.L.; O.T.L.; O.T.M.M



[1] Centro de Pesquisas Agroflorestais de Rondônia, EMBRAPA, 78900-970, Porto Velho, RO – Brazil. E‑mail: rodrigo@cpafro.embrapa.br

[2] Aracruz Celulose, 29197-900. Aracruz, ES – Brazil. E‑mail: jmuro@aracruz.com.br

[3] Departamento de Biologia Geral, Universidade Federal de Viçosa – UFV, 36570-000. Viçosa, MG – Brazil.. E‑mail: cdcruz@ufv.br / ebarros@ufv.br

[4] Universidade Federal de Viçosa ­– UFV, 36570-000. Viçosa, MG – Brazil. E-mail: willian@pq.cnpq.br

[5] Departamento de Microbiologia, Universidade Federal de Viçosa – UFV, 36570-000. Viçosa, MG – Brazil. E‑mail: ezfa@ufv.br