Author(s): Amaral, A J ; Pavao, Ana L. ; Gama, Luis
Date: 2020
Persistent ID: http://hdl.handle.net/10400.5/24098
Origin: Repositório da Universidade de Lisboa
Subject(s): Functional genomics; GWAS; Inbreeding; Local breeds; ROH; Single nucleotide polymorphisms (SNPs)
Research Areas: Agriculture ; Veterinary Sciences ; Zoology
Ramo Grande is a local cattle breed raised in the archipelago of Azores, with a small and dispersed census, where inbreeding control is of utmost importance. A single nucleotide polymorphism (SNP) Beadchip array was used to assess inbreeding, by analysis of genomic regions harboring contiguous homozygous genotypes named runs of homozygosity (ROH), and to estimate past e ective population size by analysis of linkage disequilibrium (LD). Genetic markers associated with production traits were also investigated, exploiting the unique genetic and adaptation features of this breed. A total of 639 ROH with length >4 Mb were identified, with mean length of 14.96 Mb. The mean genomic inbreeding was 0.09, and long segments of ROH were common, indicating recent inbred matings. The LD pattern indicates a large e ective population size, suggesting the inflow of exotic germplasm in the past. The genome-wide association study identified novel markers significantly a ecting longevity, age at first calving and direct genetic e ects on calf weight. These results provide the first evidence of the association of longevity with genes related with DNA recognition and repair, and the association of age at first calving with aquaporin proteins, which are known to have a crucial role in reproduction.
