• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1087-1092
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• 2003

As an experimental reference population, crosses between Korean native pig and Landraces were established and information on growth traits was recorded. Animals were genotyped for 24 microsatellite markers covering chromosomes 2, 6, and 7 for partial-genome scan to identify chromosomal regions that have effects on growth traits. quantitative trait loci (QTL) effects were estimated using interval mapping by the regression method under the line cross models with a test for imprinting effects. For test of presence of QTL, chromosome-wide and single position significance thresholds were estimated by permutation test and normal significance threshold for the imprinting test were derived. For tests against the Mendelian model, additive and dominance coefficients were permuted within individuals. Thresholds (5% chromosome-wide) against the no-QTL model for the analyzed traits ranged from 4.57 to 4.99 for the Mendelian model and from 4.14 to 4.67 for the imprinting model, respectively. Partial-genome scan revealed significant evidence for 4 QTL affecting growth traits, and 2 out of the 4 QTLs were imprinted. This study demonstrated that testing for imprinting should become a standard procedure to unravel the genetic control of multi-factorial traits. The models and tests developed in this study allowed the detection and evaluation of imprinted QTL.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.301-306
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• 2004

This study was conducted to develop new markers at the region that was related to QTL affecting intramuscular fat and backfat thickness on chromosome 6q28 - 6q32 in pigs. Dozens of repeated sequences were founded using shotgun sequencing of several BAC clones corresponding to that region, of which five new microstellite markers that identified polymorphism were discovered. The mean number of alleles at each locus observed 2.13(KP0290F2), 4.63(KP0248Cll), 7.38(KP1231C91), 2.75(KPI23IC92) and 6.2S(KP1231C93) in 8 breeds(Landrace, Korean native pig, Duroc, Yorkshire, Berkshire, Wuzhishan pig, Xiang pig, Min pig). The average estimated heterozygosity values at each locus varied from 0.2100(KP0290F2) to 0.8304(KPI23IC91) in all populations. In other hand, the average allele of all loci WlL'I within range of 0.4517(Berkshire) and 0.6957 (Yorkshire). Of these markers, KP0248C11, KP1231C91 and KP1231C93 were identified to have optimal number of alleles, high heterozygosity values and low standard deviation values. Especially, KPI23IC91 and KPI231C93 might be considered as a useful marker for genetic mapping and diversity study.