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Muhle AC Jaggy A Stricker C Steffen F Dolf G Busato A Kornberg M Mariscoli M Srenk P Gaillard C 《Veterinary journal (London, England : 1997)》2002,163(3):247-318
Sensorineural deafness is a common congenital disorder in Dalmatians and is genetically transmitted. Different modes of inheritance have been proposed and the objective of this study was to study these by segregation analyses using maximum likelihood procedures. Data from 33 complete Dalmatian families were collected and data from 56 single Dalmatians added. This resulted in a total of 575 dogs with 357 known phenotypes. All dogs were clinically evaluated and electrophysiologically tested with brainstem auditory evoked responses.The prevalence of deafness was 16.5% (9.4% unilaterally deaf, 7.1% bilaterally deaf). Females were 4.4% more affected than males but this difference was not significant. Within the same litter, different phenotypic expressions of deafness occurred, which suggested different expressions of the disease. In addition, two data sets were analysed: the first included normal, uni- and bilaterally deaf dogs, the second had normal and deaf Dalmatians. We found that a recessive allele at a single biallelic major locus fitted our data best, although an incomplete penetrance of the recessive homozygotes was observed. 相似文献
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中国家驴生长激素基因内含子2的遗传多样性分析 总被引:1,自引:0,他引:1
为了从分子水平揭示家驴的遗传多样性,本研究以中国7个家驴品种(临县驴、关中驴、新疆驴、广灵驴、淮北驴、德州驴、晋南驴)174个个体为试验动物,利用PCR-SSCP技术研究生长激素(GH)基因第2内含子的遗传多样性并进行序列分析.结果显示:第2内含子表现多态性,174个个体检测到3个单倍型,单倍型比例为1.7%.单倍型多样度以临县驴、淮北驴较高,分别为0.678和0.542.广灵驴与关中驴的单倍型多样度(Haplotype diversity,H)比较接近,分别为0.409和0.462.其次为德州驴和晋南驴,分别为0.355和0.304,新疆驴最低为0.077.对该片段的纯合型分别测序发现,B单倍型在第735位碱基G→C.A单倍型在869位碱基G→T.上述结果首次证实驴GH基因内含子2存在多态性. 相似文献
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H. Mochizuki A. Motsinger‐Reif C. Bettini S. Moroff M. Breen 《Veterinary and comparative oncology》2017,15(3):829-839
The aim of this study was to evaluate the relationship between breed and the histopathological grade of canine mast cell tumours (MCTs). A retrospective survey of pathology data of 9375 histopathologically confirmed diagnoses of cutaneous MCTs in the US was evaluated in the context of breed prevalence in over two million registered purebred dogs. Association of histopathological grade with breed, age, sex and spay/neuter status was assessed. The data indicate that the proportion of high‐grade tumours increases with advancing age, and that male and intact dogs have increased odds of developing high‐grade tumours. A significant difference in the proportion of high‐grade tumours between breeds was detected. The Pug was at significantly increased risk of developing low/intermediate‐grade tumours, but not high‐grade tumours, resulting in preponderance of less aggressive MCTs in this breed. The results of this study suggest a genetic association for the development of high‐grade MCTs. 相似文献
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猪瘟是猪的最严重疾病之一,其病原 是猪瘟病毒,基因组为单股正链RNA。猪瘟 弱毒疫苗在猪瘟的免疫防治中发挥了巨大作 用,但由于弱毒疫苗免疫的动物不能从血清 学上与自然感染动物区分,使其应用受到很 大限制,研制标记疫苗是解决这个问题的重 要途径。由于RAN的结构不稳定成为阻碍 RNA病毒研究的主要障碍,所以病毒分子生 物学是新型猪瘟疫苗研究的必要手段。近年 来兴起的逆向遗传研究将RNA病毒的基因 组转化为cDNA,文章就猪瘟病毒逆向遗传 研究的意义、方法、概况及其在猪瘟新型疫苗 研究中的应用进行了全面综述。 相似文献
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Peter M. Visscher Naomi R. Wray Chris S. Haley 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(4):273-278
Through his own research contributions on the modelling and genetic analysis of quantitative traits and through his former students and postdocs, Robin Thompson has indirectly left a major legacy in human genetics. In this short note, we highlight examples of the long‐lasting relevance and impact of Robin's work in human genetics. A lone early study of marker‐assisted selection developed many of the tools and approaches later exploited (often after reinvention) by the human genetics community in GWAS studies and for prediction. Furthermore, a particularly clear example of the pervasive impact of Robin's work is that REML has become the default method to estimate variance components and that genetic predictions exploiting linkage disequilibrium in the population are starting to become used in precision medicine applications. 相似文献