Oligogenic transmission of abnormal teat patterning phenotype (ATPP) in cattle

Abnormal teat patterning phenotype (ATPP) is characterized by one (moderate form) or two (severe form) absent teats in cattle. Using an allele-sharing non-parametric linkage strategy, significant associations with severe ATPP animals were detected on BTA17 (Z(max) = 7.3 at 21 cM), centromeric BTA1 (Z(max) = 3.7 at 8 cM) and telomeric BTA1 (Z(max) = 4.8 at 142 cM). The BTA17 region was also significantly associated in the analysis of the moderate ATPP animals (Z(max) = 5.3 at 0 cM). The transmission disequilibrium test in severe ATPP animals demonstrated significant over-transmission of paternal alleles in the BTA17 region (P = 2.2 x 10(-9)), the centromeric BTA1 region (P = 0.035) and the telomeric BTA1 region (P = 0.005). Significant over-transmission of the BTA17 region was also observed among the moderate ATPP animals (P = 2.3 x 10(-4)). These findings indicate that the BTA17 locus plays a key role in risk of the disease, and that the BTA17 locus contributes temporally in combination with the two other loci on BTA1 and/or possibly unknown modifier(s) in a probabilistic oligo- or polygenic manner of transmission. Haplotypes of these three loci can be used for marker-assisted animal breeding to control the recurrence of affected progeny with ATPP.