Evaluation of the ovine callipyge locus: I. Relative chromosomal position and gene action.
Evaluation of the ovine callipyge locus: I. Relative chromosomal position and gene action.
复制标题
绵羊 callipyge 基因座的评估：I.相对染色体位置和基因作用。
DOI：
10.2527/1998.7682062x
复制
发表时间：
1998
影响因子：
3.3
通讯作者：
K. Leymaster
中科院分区：
文献类型：
--
作者：
B. Freking;B. Freking;J. Keele;C. Beattie;S. Kappes;T. P. Smith;T. Sonstegard;M. K. Nielsen;K. Leymaster
收集了基因分型和表型数据，以估计Callipyge(CLPG)基因的染色体位置，并测试基因的作用。9只极肌肉发达的多赛特公羊和114只罗曼诺夫母羊组成了在CLPG基因座分离的362只F2羔羊资源群的祖辈。亲代由8个F1父本和138个F1母猪组成。从23周龄开始，将F2代羔羊分成六组，每隔3周连续屠宰一次，以便在不同的终点进行比较。建立了绵羊18号染色体上25个标记座位(平均每个标记708个信息减数分裂)的连锁群，其长度为87.2 cM，改进了已知的标记顺序的覆盖率和精确度以及与已有的绵羊18号染色体图谱的间隔距离。统计模型包括年份、性别、父系、回归对基因型概率的影响，以及特定于基因型的线性回归和二次回归对适当的协变量的影响。CLPG基因效应的正交对比评估了基因作用的加性、母体显性和父本派生的极性超显性模型。最简约的模型没有包括加性和母体显性遗传对比。通过对四个关键性状的分析，得出了CLPG相对于最着丝粒标记的位置为86 cM的共识。以腿部评分为因变量，在86 cm处，以3 df代表极优势的F检验最大(F=407.4；P<；0.00001)。这些结果与CLPG基因座位于18号染色体端粒区的结果一致，并支持Cockett等人提出的基因作用的极性超显性模型。(1996年)。此外，具有明确表型的重组个体将CLPG的位置限制在3.9厘米的间隔内，从而促进了位置克隆实验。
Genotypic and phenotypic data were collected to estimate chromosomal position of the callipyge (CLPG) gene and to test gene action. Nine Dorset rams of extreme muscling phenotype and 114 Romanov ewes composed the grandparent generation of a resource flock of 362 F2 lambs segregating at the CLPG locus. The parent generation consisted of eight F1 sires and 138 F1 dams. The F2 lambs were serially slaughtered in six groups at 3-wk intervals starting at 23 wk of age to allow comparisons at different end points. A linkage group of 25 marker loci (mean of 708 informative meioses per marker) spanning 87.2 cM was developed and improved the previous known coverage and precision of marker order and interval distance from available maps of ovine chromosome 18. Probabilities of each CLPG genotype were calculated at 1-cM intervals (0 to 107 cM). Statistical models included effects of year, sex, sire, regressions on genotypic probabilities, and genotype-specific linear and quadratic regressions on appropriate covariates. Orthogonal contrasts of CLPG genotypic effects evaluated additive, maternal dominance, and paternally derived polar overdominance models of gene action. The most parsimonious model did not include the additive and maternal dominance genetic contrasts. From analyses of four key traits, a consensus for position of CLPG was obtained at 86 cM relative to the most centromeric marker. An F-test with 3 df representing polar overdominance was maximum at position 86 cM (F = 407.4; P < .00001) with leg score as the dependent variable. These results are consistent with assignment of the CLPG locus to the telomeric region of chromosome 18 and support the polar overdominance model of gene action proposed by Cockett et al. (1996). Furthermore, recombinant individuals with definitive phenotypes confined the position of CLPG to a 3.9-cM interval, facilitating positional cloning experiments.
小鼠 Cd7 映射到 11 号染色体。
影响因子：
3.2
作者：
Lee,DM;Watson,ML;Seldin,MF
通讯作者：
Seldin,MF