Analysis on Polymorphisms of GHR Gene in Improved Hybrid Yellow Cattle Groups from Liupan Mountain Area in Ningxia

[Objective] The paper aimed to analyze the polymorphism of the growth hormone receptor （GHR） in improved hybrid yellow cattle group from Liupan Mountain area in Ningxia Autonomous Region,so as to provide technological basis for hybrid improvement. [Method] Polymerase chain reaction-restriction fragment length polymorphisms （PCR-RFLP） technology was carried out to examine polymorphisms of GHR gene of 70 individuals. [Result] The target fragment of 338 bp was amplified. The PCR product digested by restriction enzyme Alu I showed polymorphisms. The frequencies of the two genotypes （AA,BB） were 75.71% （53 individuals） and 24.29% （17 individuals）,respectively. [Conclusion] Two genotypes of GHR gene were detected in improved hybrid yellow cattle groups from Liupan Mountain area in Ningxia.

Sequencing and Analysis of G HR Gene from Genomic DNA Pools of Mink

In order to study the single nucleotide polymorphisms （SNPs） of growth hormone receptor （GHR） gene in mink populations, genomic DNA pools of Minghua black minks and silver-blue minks were constructed, and the 10^th exon of GHR gene was PCR amplified from the two DNA pools and sequenced. The results showed that two SNPs were found at position 209 （T/C） and position 533 （C/A） of the 10^th exon of GHR gene in the two mink populations.

Study on the Developmental Changes of Muscular GHR mRNA Expression in Sheep

[ Objective] The study aimed to explore the expression of muscular growth hormone receptor gene （GHR） in sheep at the early stage of growth and development. [Method] The GHR mRNA expression levels in longissimus dorsal muscles of male Kazak sheep and Xinjiang fine wool sheep with different ages were quantitatively analyzed by real time PCR. [ Result] Sheep GHR mRNA expression level in longissimus dorsal muscle increased firstly followed by decline, and then kept steady until the end of the experiment, with the expression peak appearing on postnatal day 30. The GHR mRNA expression level of Kazak sheep was extremely lower than that of Xingjiang fine wool sheep from 2 to 90 days old （ P 〈0.01 ）. E Conclusionl Both age and breed had great effects on the expression of muscular GHR gene in sheep.

Developmental Changes of GHRmRNA Expression Level in Sheep Liver

[Objective] To detect the expression of liver growth hormone receptor gene （GHR） during the eady development of Kazak sheep and Xinjiang fine-wool sheep, and thus provide information for the research about the early growth and development of sheep. [ Method] With real-time quantitative PCR, the liver GHR mRNA level was separately detected in two varieties of sheep at 2, 30, 60, 90 and 120 days old. Then the data was analyzed with SPSS software. E Result] The liver GHR gene was highly expressed in 2 day-old sheep, but the expression level fell to the lowest point at 30 days old and then rose continuously; the change trend after 30 days old was positively correlated with the cumulative growth curves of sheep （ P 〈0.05） ; GHR mRNA level was lower in Kazak sheep than in Xinjiang fine-wool sheep during 2 -90 days old, but the difference was ex- tremely significant （P 〈0.01 ） only at 2 days old and 90 days old. [ Conclusion] The male Kazak sheep and Xinjiang fine-wool sheep have similar model of developmental changes of liver GHR mRNA and the differences are smaller between these two species; GHR gene may play an important role in the regulation of sheep growth.