Detection of three major chromosome regions involved in the arrival to puberty in bulls through genome-wide association.

FERNANDEZ M E; LIRON J P; PRANDO A J; ROGBERG MUÑOZ A; BALDO A; GIOVAMBATTISTA G

Cairns

Congreso; 33rd Conference of the International Society of Animal Genetics; 2012

Society for Animal Genetics

In bovine, there are signifcant differences, among and within breeds, in time when bulls reach puberty. The objective of this work was to perform a genomewide association study using a selective DNA approach for identifcation of genetic markers associated with age at puberty. Two hundred seventy-six Angus males were weighed and scrotal circumference measured every month. When frst bull calves reached 26 cm of SC, sperm quality was added to the monthly measurements for the next 3 mo. Based on sperm quality, 2 groups, corresponding to the top and bottom 6.5% of the phenotypic distribution, were chosen. These samples were genotyping with the Illumina BovineHD Genotyping BeadChip. The number of associated SNP at 0.001 signifcance thresholds was 265, among which 6 were signifcant at 0.0001. These signifcant associated markers were located majorly in 5 chromosome regions: BTA3 (30.57% of associated SNPs), BTA24 (29.43%), and BTA1, 16 and 20 (23.77%). Fifteen additional chromosomes only had few associated SNPs, while the remaining 10 chromosomes did not exhibit signifcant associ- ated markers. SNPs located into the BTA3, 20 and 24 associated regions were validated in the whole sample using pyrosequencing methods. The results obtained here will be useful for further identifcation of causative mutations and functional studies.