Current research areas

  • Development of new genetic/genomic analytical tools

    Far from focusing on a specific domestic species, my research interests rely on the development and implementation of statistical approaches for a better understanding of the genomic architecture of animals. I have already worked on genetic/genomic evaluation, gene expression data, canalization models, segregation analysis, mutational patterns, partitioning of inbreeding depression, circular data, proportional hazard models, and threshold traits, among others. Most of my developments are based on Bayesian statistics...

  • Integrative omics for reproductive and carcass traits in Iberian pigs

    Genomics, metabolomics, microbiomics and phenomics... all together to improve the reproduction and carcass traits of Iberian pigs. This is a collaboration with colleagues from Universidad de Zaragoza (Zaragoza, Spain), Universitat Politècnica de València (Valencia, Spain) and Institute of Agrifood Research and Technology (IRTA, Lleida, Spain). Data come from Inga Food SA (Almendralejo, Spain), a private company owning the biggest herd of Iberian pigs in Spain.

  • Transmission ratio distortion in cattle

    Genomic screening of regions involved in abnormal inheritance patterns (i.e., non-Mendelian). This will unravel fertility-related genes with potential contributions to current cattle industry. Indeed, this is coordinated by the Department of Animal Biosciences of the University of Guelph (Guelph, Canada) and merges efforts from leader dairy and beef companies such as as Semex (Guelph, Canada) and Angus Genetics, Inc. (Saint Joseph, MO, USA), with

Selected publications

● Casellas J, Martín de Hijas-Villalba M, Vázquez-Gómez M, Id-Lahoucine S (2021) Low-coverage whole-genome sequencing in livestock species for individual traceability and parentage testing. Livest. Sci. 251: 104629.
● Casellas J, Id-Lahoucine S, Cánovas A (2020) Discriminating between allele- and genotype-specific transmission ratio distortion. Anim. Genet. 51: 847-854.
● Id-Lahoucine S, Molina A, Cánovas A, Casellas J (2019) Screening for epistatic selection signatures: a simulation study. Scientific Rep. 9: 1026.
● Casellas J, Cañas-Álvarez JJ, Fina M, Piedrafita J, Cecchinato A (2017) Fine mapping by composite genome-wide association analysis. Genet. Res. 99: e4.
● Casellas J, Esquivelzeta C, Legarra A (2013) Accounting for new mutations in genomic prediction models. J. Dairy Sci. 96: 5389-5402.
● Casellas J, Varona L (2012) Modeling skewness in gene expression data analyses. PLoS One 7: e38919.
● Casellas J (2007) Survival quantitative trait loci fine mapping by measuring and testing for Hardy-Weinberg and linkage disequilibrium. Genetics 176: 721-724.


● Id-Lahoucine S, Schaeffer LR, Cánovas A, Casellas J (2022) Analyses of lambing dates in sheep breeds using von Mises distribution. J. Anim. Breed. Genet. 139: 271-280.
● Casellas J, Id-Lahoucine S, Martín de Hijas-Villalba M (2019) Analysis of lambing distributionin the Ripollesa sheep breed. II. Environmental and genetic sources of variation. Animal 13: 2140-2145.
● Casellas J, Martín de Hijas-Villalba M, Id-Lahoucine S (2019) Analysis of lambing distributionin the Ripollesa sheep breed. I. Development and comparison of circular von Mises models. Animal 13: 2133-2139.
● Marí P, Casellas J (2018) Freemartinism in replacement ewe-lambs of the Ripollesa sheep breed. J. Vet. Sci. 19: 858-861.
● Id-Lahoucine S, Casellas J (2017) Impact of incomplete pedigree data and independent culling level pre-selection on the genetic evaluation of livestock: A simulation study on lamb growth. Livest. Sci. 198: 76-81.
● Casellas J (2016) Comparison between linear and proportional hazard models for the analysis of age at first lambing in the Ripollesa breed. Animal 10: 365-371.


● Varona L, Altarriba J, Moreno C, Martínez-Castillero M, Casellas J (2019) A multivariate analysis with direct additive and inbreeding depression load. Genet. Sel. Evol. 51: 78.
● Id-Lahoucine S, Cänovas A, Janton C, Miglior F, Fonseca PAS, Sargolzaei M, Miller S, Schenkel FS, Medrano JF, Casellas J (2019) Implementation of Bayesian methods to identify SNP and haplotype regions with transmission ratio distortion across the whole genome: TRDscan v.1.0. J. Dairy Sci. 102: 3175-3188.
● Casellas J, Cañas-Álvarez JJ, González-Rodríguez A, Puig-Oliveras A, Fina M, Piedrafita J, Molina A, Díaz C, Baró J, Varona L (2017) Bayesian analysis of parent-specific transmission ratio distortion in seven Spanish beef cattle breeds. Anim. Genet. 48: 93-96.


● Vázquez-Gómez M, Martín de Hijas-Villalba M, Varona L, Ibáñez-Escriche N, Rosas JP, Negro S, Noguera JL, Casellas J (2020) Maternal transmission ratio distortion in two Iberian pig varieties. Genes 11: 1050.
● Casellas J, Ibáñez-Escriche N, Varona L, Rosas JP, Noguera JL (2019) Inbreeding depression load for litter size in Entrepelado and Retinto Iberian pig varieties. J. Anim. Sci. 97: 1979-1986.
● Casellas J, Manunza A, Mercader A, Quintanilla R, Amills M (2014) A flexible Bayesian model for testing for transmission ratio distortion. Genetics 198: 1357-1367.
● Casellas J, Martínez-Giner M, Pena RN, Balcells I, Fernández-Rodríguez A, Ibáñez-Escriche N, Noguera JL (2013) Variability-specific differential gene expression across reproductive stages in sows. Animal 7: 378-385.


● Casellas J (2018) On individual-specific prediction of hidden inbreeding depression load. J. Anim. Breed. Genet. 135: 37-44.
● Casellas J, Vidal-Roqueta D, Flores E, Casellas-Vidal D, Llach-Vila M, Salgas-Fina R, Casellas-Molas P (2011) Epistasis for founder-specific inbreeding depression in rabbits. J. Hered. 102: 157-164.


● Casellas J, Gianola D, Medrano JF (2014) Bayesian analysis of additive epistasis arising from new mutations in mice. Genet. Res. 96: e008.
● Casellas J, Gularte RJ, Farber CR, Varona L, Mehrabian M, Schadt EE, Lusis AJ, Attie AD, Yandell BS, Medrano JF (2012) Genome scans for transmission ratio distortion regions in mice. Genetics 191: 247-259.
● Casellas J, Farber CR, Verdugo RA, Medrano JF (2010) Segregation analysis of a sex ratio distortion locus in congenic mice. J. Hered. 101: 351-359.
● Casellas J, Farber CR, Gularte RJ, Haus KA, Warden CH, Medrano JF (2009) Evidence of maternal QTL affecting growth and obesity in adult mice. Mamm. Genome 20: 269-280.
● Casellas J, Medrano JF (2008) Within-generation mutation variance for litter size in inbred mice. Genetics 179: 2147-2155.


Full List (19/MAY/22)

Mentored students

  • Doctor of Philosophy degrees

    Xavier Fernández de Sevilla (2008)

    Selection objectives for animal welfare in the pig industry


    Cecilia Esquivelzeta (2012)

    Morphology, carcass and meat characterization in the Ripollesa sheep breed


    Marta Fina (2013)

    Optimization of genetic evaluation in the Bruna dels Pirineus beef cattle breed


    Mayela del Carmen Castillo (2017)

    Modelization of mutational variability depending on parents' age in two mammalian species

  • Masters of Science degrees

    Samir Id Lahoucine (2016)

    Detecting signatures of selection in genes under epistatic interaction by simulation in cattle breeds


    ToniMarie Ebbole (2016)

    Analysis of interferences among sires in paternity testing procedures by SNP genotypes


    Melani Martín de Hijas (2017)

    Weighting SNP panels for genomic prediction by simulated annealing




Once upon a time...

  • This was me when I collected data for my M.S. dissertation about piglet survival... (early 2002)