The chromosomes are separated with alternating colours. The resulting phenotypes can be considered as breeding values for the bulls. Pigmentation around the eyes is highly correlated with eye-lid and corneoscleral pigmentation [22]. DNA samples were available for FV animals only. The marker allele causing the gain of an upstream polyadenylation signal is associated with a lower pCE EBV, i.

The mapping was facilitated by applying breeding values for paternal calving ease to compensate the low heritability of calving traits. Holmberg M, Andersson-Eklund L Quantitative trait loci affecting fertility and calving traits in Swedish dairy cattle. Variants of this gene may predispose to lactating SNTs, which are particularly undesirable. Klein R Power analysis for genome-wide association studies. Genotypes were available for , SNPs. The study population consisted of bulls of the FV breed with a total of , progeny with phenotypes for ACOP.

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The higher incidence of SNTs in cows born from later parities [2] may therefore be explained by a stronger response to lactational hormones of Wnt signalling in pertinently predisposed animals.

Tuesday 19 December at 9. In summary, these findings show that precisely defined phenotypes are indispensable for the replication of association signals in validation populations which is also emphasized by Barendse [94]. Genotypes for SNPs resulting from re-sequencing were determined in animals and imputed for the remaining animals of the study population.

Nevertheless, fine mapping of QTL regions and subsequent identification of underlying genetic variants requires independent validation populations to distinguish between true and linked polymorphisms []. The distribution of loci with large effects is a major issue for the the appropriate model selection for genomic prediction in cattle populations.


Qianqian Zhang: Towards Cattle Precision Breeding Using Next Generation Sequencing

American Journal of Physical Anthropology American Journal of Human Genetics While SNTs in cattle negatively affect milking ability and dlssertation as bacteria reservoir [75],[76], teat number and hubrt morphology are important dissertatino traits in swine breeding programs [77].

Since marker alleles with negative effect on pCE have positive effects on growth-related traits, the QTL may exert their effects on the birthing process through fetal growth traits. Allele frequencies between half-sib families might differ considerably and thereby confound QTL mapping by causing spurious associations [51].

Genotypes and quality control Genotyping was performed with three different genotyping arrays. The mixed model based approach outperformed the PCA based approach.

Genome Research, 17 4pp. Thus, the current assembly must still be considered as a draft version.

Qianqian Zhang: Towards Cattle Precision Breeding Using Next Generation Sequencing

Polymorphisms within the coding region of LEF1 have already been shown to be associated with the occurrence of inverted teats in swine [37]. Haplotype analysis Haplotype analysis was carried out for the associated regions on chromosome 14 and 21 in an attempt to delineate the chromosomal segment carrying the pCE Ddissertation.

The four QTL explain a substantial fraction of the genetic variation of supernumerary teats.

dissertation hubert pausch

The successful imputation of high-density genotype information increased the power of the GWAS and enabled the mapping of QTL that account for a minor part of the genetic variation only. These fractions are distinctly higher than those reported for traits with similar heritability in human genetics [49] [1].


Quantile — quantile plots of the expected vs. Bennett GL Experimental selection for calving ease pauscb postnatal growth in seven cattle populations.

dissertation hubert pausch

A Map of genes contained in this region. Hubert Pausch has a forward-looking vision of customized livestock breeding. This diasertation a strong indication for the causal variant lowering the pCE EBV to exclusively reside on this haplotype version.

Two major QTL were identified on bovine chromosomes 14 and 21 after careful correction for population stratification applying a principal components analysis PCA based approach. Figure 2 presents the frequency distribution of animals with an increasing number of SNTs-predisposing alleles from 0 to 8. Vissertation New York, N. However, the identification of QTL that either affect prenatal or postnatal growth but not both would facilitate to efficiently improve postnatal beef performance without antagonistically compromising calving ease.

Genome-wide association studies in cattle populations In cattle, GWAS have been successfully applied to identify genomic regions underlying both mendelian e. Pigmentation around the eyes is highly correlated with eye-lid and corneoscleral pigmentation [22].

Population stratification within the study population. The number of SNPs used for the evaluation of the imputation accuracy is given for each chromosome in Table S4. DYDs for UC were available for animals. You always supported me without reserve and you remind me that life consists of much more than work alone.