- "Fine-mapping quantitative trait loci for twinning rate on Bos taurus chromosome 14 in North American Holsteins"
Bierman CD, Kim E, Weigel K, Berger PJ, Kirkpatrick BW, Journal of Animal Science 88(8): 2556-2564 Aug 2010. Based on single-marker results from data II, BTA14 harbors QTL responsible for approximately 24% of the variation in twinning rate predicted transmitting ability.
- "A cattle family in New Zealand with triplet calving abilities"
Morris CA, Wheeler M, Levet GL, et al., Livestock Science 128 (1-3): 193-196 Mar 2010. This paper reports on calving data from a cow family in New Zealand which is elite for triplet calving ability. The foundation cow (named 'Treble') was born in 1993 and her calvings included three sets of triplets. A triplet son (named 'Trio'), born in 1996, was used for matings in two New Zealand herds, producing 44 daughters which were retained for breeding, and these had a total of 109 calvings by 2008.
- "Geonme-wide scan for bovine twinning rate QTL using linkage disequilibrium"
Kim ES, Berger PJ, Kirkpatrick BW, Animal Genetics 40 (3): 300-307 Jun 2009. To identify genomic regions or genes associated with twinning rate, QTL analysis based on linkage combined with linkage disequilibrium ( LLD) and individual marker associations was conducted across the genome using high-throughput single nucleotide polymorphism ( SNP) genotypes. Keywords: Quantitative Trait Loci; Ovulation Rate QTL; Dense Marker Maps; Single Nucleotide Polymorphism; Twin.
- "Linkage disequilibrium in the North American Holstein population"
Kim ES, Kirkpatrick BW, Animal Genetics 40 (3): 279-288 Jun 2009. Linkage disequilibrium was estimated using 7119 single nucleotide polymorphism markers across the genome and 200 animals from the North American Holstein cattle population. Keywords: Quantitative Trait Loci; Human genome; Haplotype Blocks; Cattle Breeds; Linkage Disequilibrium; Nucleotide Polymorphism.
- "Refined mapping of twinning-rate quantitative trait loci on bovine chromosome 5 and analysis of insulin-like growth factor-1 as a positional candidate gene"
Kim ES, Shi X, Kirkpatrick BW, et al., Journal of Animal Science 87 (3): 835-843 Mar 2009. Using a large number of animals, an increased density of SNP marker association tests, and a combined linkage and linkage disequilibrium mapping method, the position of QTL was defined in the North American Holstein population. Keywords: Ovulation Rate; Cattle; Prediction; Genome; Linkage; Identity; Map.