Submitted to: Swine in Biomedical Research Conference
Publication Type: Abstract Only
Publication Acceptance Date: 5/23/2011
Publication Date: 7/17/2011
Citation: Rohrer, G.A., Nonneman, D.J., Wiedmann, R.T. 2011. Identification of genomic regions associated with cryptorchidism in pigs. Proc., Swine in Biomedical Research Conference. p. 37-38.
Technical Abstract: Cryptorchidism, failure of one or both testes to descend into the scrotum, is a common abnormality in pigs and man. Research has shown that genetics contributes to the incidence of the defect. Unlike humans, porcine cryptorchidism is not typically associated with other physiological defects. Yet cryptorchidism does result in decreased value of animals and other production losses. A family of the U.S. Meat Animal Research Center’s Landrace-Duroc-Yorkshire composite population with moderate inbreeding frequently produces cryptorchid pigs (34% incidence). In an attempt to identify genomic regions segregating with cryptorchidism, 12 affected, eight control siblings and all parents from this family were genotyped using the Illumina SNP60K BeadChip along with three affected animals and their parents from an unrelated litter. Association analyses were conducted with PLINK using the dfam option. Analyses were done with and without the three unrelated affected animals. A comparison of the results revealed that the unrelated animals reduced the significance values considerably, due to a different locus affecting cryptorchidism or different linkage disequilibrium between SNP markers and the causative genetic variation. Among the 28,304 mapped SNP markers that segregated within this family, numerous associations (p < 0.006 nominal significance) were found at SSC2:5.0-16.4 Mb (n=33) and SSC10:26.5-46.2Mb (n=68). An additional 136 affected, 222 controls and their parents (65 sires and 114 dams) were genotyped with 25 SSC2 and 10 SSC10 markers. The most significant marker was located at SSC10:27.4 Mb (p < 0.005). Additional markers are being tested and affected animals will be added as they are identified. *USDA is an equal opportunity provider and employer.