Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such nar...Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such narrow region to fine map milk production QTLs with 15 SNPs across 25 Mb with each SNP in 1 Mb within most regions in a Chinese Holstein population with daughter design. 1 449 Holstein cows and 11 sires were genotyped for such SNPs by using TaqMan probe and RFLP assays. Multipoint linkage analysis across family revealed a QTL affecting milk yield between PPARGC1A C4075T and SLC34A2 T1713C. Meanwhile, within family analysis found three milk yield QTLs （two in CR T60984131G-CEP135 C501T and one in PDLIM5 A106C-OPN T3907, a fat yield QTLin UGDH T1670C-CR T60984131G region, and two protein yield QTLs in TBC1D1 G501C-UGDH T1670C and PPARGC1A C4075T-SLC34A2 T1713C, respectively. Associations between aforementioned significant SNP markers and milk production traits were further implemented. We found significant associations of PPARGC1A C4075T, SLC34A2 T1713C with milk yield （P0.05, P0.01, P0.01）, UGDH T1670C, and CR T60984131G with fat yield （P0.01, P0.01）, and PPARGC1A C4075T, SLC34A2 T1713C, UGDH T1670C and OPN T3907 with protein yield （P0.01, P0.01, P0.01, P0.01）. Our findings implied that QTLs affecting milk production traits on BTA6 were pleictropism or multigenic effect and PPARGC1A and OPN may be the causal mutations behind milk production QTLs on BTA6 in the Chinese Holstein population.展开更多
A Chinese Holstein population with daughter design was analyzed using 14 microsatellites covering a map distance of 55.7 cM on chromosome 6 to fine map QTL for five milk production traits. 26 paternal half-sib familie...A Chinese Holstein population with daughter design was analyzed using 14 microsatellites covering a map distance of 55.7 cM on chromosome 6 to fine map QTL for five milk production traits. 26 paternal half-sib families with 2356 daughters were involved. Two different approaches, linear regression approach and variance component ap-proach, were employed, with a one-QTL model and two-QTL model fitted. With a one-QTL model, the linear regression approach revealed a QTL near BMS470 with effects on milk yield, fat yield, protein yield, and fat percentage, and another QTL near BMS2460 for protein percentage. The variance component approach confirmed the results of linear regres-sion approach for the three yield traits, with the exception that the QTL for fat yield was mapped to a different position near BMS1242. The 95% confidence intervals resulted from linear regression, obtained by bootstrapping, were generally large, ranging from 31 to 53 cM, whereas the variance com-ponent approach revealed very small confidence intervals, calculated by LOD drop-off method, for the three yield traits, only 4―5 cM. With a two-QTL model, both approaches pro-vided strong evidence for the existence of two QTLs for the three yield traits. Along with the QTLs identified in one-QTL model analyses, the linear regression approach revealed a second QTL near BP7 with effects on all the three yield traits, whereas the variance component approach located the sec-ond QTL near ILSS035, BMS470, and BP7 for the three traits, respectively.展开更多
Background:Economically important milk production traits including milk volume,milk fat and protein yield vary considerably across dairy goats in New Zealand.A significant portion of the variation is attributable to g...Background:Economically important milk production traits including milk volume,milk fat and protein yield vary considerably across dairy goats in New Zealand.A significant portion of the variation is attributable to genetic variation.Discovery of genetic markers linked to milk production traits can be utilised to drive selection of highperformance animals.A previously reported genome wide association study across dairy goats in New Zealand identified a quantitative trait locus(QTL)located on chromosome 19.The most significantly associated single nucleotide polymorphism(SNP)marker for this locus is located at position 26,610,610(SNP marker rs268292132).This locus is associated with multiple milk production traits including fat,protein and volume.The predicted effect of selection for the beneficial haplotype would result in an average production increase of 2.2 kg fat,1.9 kg protein and 73.6 kg milk yield.An outstanding question was whether selection for the beneficial allele would co-select for any negative pleiotropic effects.An adverse relationship between milk production and udder health traits has been reported at this locus.Therefore,a genome wide association study was undertaken looking for loci associated with udder traits.Results:The QTL and production associated marker rs268292132 was identified in this study to also be associated with several goat udder traits including udder depth(UD),fore udder attachment(FUA)and rear udder attachment(RUA).Our study replicates the negative relationship between production and udder traits with the high production allele at position 19:26,610,610(SNP marker rs268292132)associated with an adverse change in UD,FUA and RUA.Conclusions:Our study has confirmed the negative relationship between udder traits and production traits in the NZ goat population.We have found that the frequency of the high production allele is relatively high in the NZ goat population,indicating that its effect on udder conformation is not significantly detrimental on animal health.It will however be 展开更多
基金supported by the National 948 Project of China (2006-G48)the National Key Technologies R&D Program of China (2006BAD04A01)+1 种基金the Key Development of New Transgenic Breeds Program of China (2009ZX08009-156B)the National Natural Science Foundation of China (31072016)
文摘Our previous studies demonstrated that the region around markers BMS470 and BMS1242 on BTA6 showed a linkage to 305-d milk yield and composition traits in the Chinese Holstein population. We herein focused on such narrow region to fine map milk production QTLs with 15 SNPs across 25 Mb with each SNP in 1 Mb within most regions in a Chinese Holstein population with daughter design. 1 449 Holstein cows and 11 sires were genotyped for such SNPs by using TaqMan probe and RFLP assays. Multipoint linkage analysis across family revealed a QTL affecting milk yield between PPARGC1A C4075T and SLC34A2 T1713C. Meanwhile, within family analysis found three milk yield QTLs （two in CR T60984131G-CEP135 C501T and one in PDLIM5 A106C-OPN T3907, a fat yield QTLin UGDH T1670C-CR T60984131G region, and two protein yield QTLs in TBC1D1 G501C-UGDH T1670C and PPARGC1A C4075T-SLC34A2 T1713C, respectively. Associations between aforementioned significant SNP markers and milk production traits were further implemented. We found significant associations of PPARGC1A C4075T, SLC34A2 T1713C with milk yield （P0.05, P0.01, P0.01）, UGDH T1670C, and CR T60984131G with fat yield （P0.01, P0.01）, and PPARGC1A C4075T, SLC34A2 T1713C, UGDH T1670C and OPN T3907 with protein yield （P0.01, P0.01, P0.01, P0.01）. Our findings implied that QTLs affecting milk production traits on BTA6 were pleictropism or multigenic effect and PPARGC1A and OPN may be the causal mutations behind milk production QTLs on BTA6 in the Chinese Holstein population.
基金This work was supported by the National Natural Science Foundation for Distin-guished Young Scholars(Grand No.30025003)the National Key Basic Research Program(Grant No.G200001603)the Hi-Tech Research and Development Program of China(Grand No.2001AA24301l).
文摘A Chinese Holstein population with daughter design was analyzed using 14 microsatellites covering a map distance of 55.7 cM on chromosome 6 to fine map QTL for five milk production traits. 26 paternal half-sib families with 2356 daughters were involved. Two different approaches, linear regression approach and variance component ap-proach, were employed, with a one-QTL model and two-QTL model fitted. With a one-QTL model, the linear regression approach revealed a QTL near BMS470 with effects on milk yield, fat yield, protein yield, and fat percentage, and another QTL near BMS2460 for protein percentage. The variance component approach confirmed the results of linear regres-sion approach for the three yield traits, with the exception that the QTL for fat yield was mapped to a different position near BMS1242. The 95% confidence intervals resulted from linear regression, obtained by bootstrapping, were generally large, ranging from 31 to 53 cM, whereas the variance com-ponent approach revealed very small confidence intervals, calculated by LOD drop-off method, for the three yield traits, only 4―5 cM. With a two-QTL model, both approaches pro-vided strong evidence for the existence of two QTLs for the three yield traits. Along with the QTLs identified in one-QTL model analyses, the linear regression approach revealed a second QTL near BP7 with effects on all the three yield traits, whereas the variance component approach located the sec-ond QTL near ILSS035, BMS470, and BP7 for the three traits, respectively.
基金co-funded by the Dairy Goat Co-operative,Ministry of Business,Innovation&Employment(3709153)the Ministry for Primary Industries Sustainable Food and Fibre Futures Fund(5000835)。
文摘Background:Economically important milk production traits including milk volume,milk fat and protein yield vary considerably across dairy goats in New Zealand.A significant portion of the variation is attributable to genetic variation.Discovery of genetic markers linked to milk production traits can be utilised to drive selection of highperformance animals.A previously reported genome wide association study across dairy goats in New Zealand identified a quantitative trait locus(QTL)located on chromosome 19.The most significantly associated single nucleotide polymorphism(SNP)marker for this locus is located at position 26,610,610(SNP marker rs268292132).This locus is associated with multiple milk production traits including fat,protein and volume.The predicted effect of selection for the beneficial haplotype would result in an average production increase of 2.2 kg fat,1.9 kg protein and 73.6 kg milk yield.An outstanding question was whether selection for the beneficial allele would co-select for any negative pleiotropic effects.An adverse relationship between milk production and udder health traits has been reported at this locus.Therefore,a genome wide association study was undertaken looking for loci associated with udder traits.Results:The QTL and production associated marker rs268292132 was identified in this study to also be associated with several goat udder traits including udder depth(UD),fore udder attachment(FUA)and rear udder attachment(RUA).Our study replicates the negative relationship between production and udder traits with the high production allele at position 19:26,610,610(SNP marker rs268292132)associated with an adverse change in UD,FUA and RUA.Conclusions:Our study has confirmed the negative relationship between udder traits and production traits in the NZ goat population.We have found that the frequency of the high production allele is relatively high in the NZ goat population,indicating that its effect on udder conformation is not significantly detrimental on animal health.It will however be
