Reseach On The Association Among Polymorphisms Of Androgen Receptor Gene,the Levels Of Gonadal Hormone And Musk Yield In The Moschus Berezovskii(Forest Musk Deer)

Forest musk deer (Moschus berezovskii) is an extremely important animal resource inChina, with a unique value. Currently, it has the largest scale of farming and the largestnumber of musk deer species. The musk secreted by male forest musk deer, is widely usedin traditional asia medicine and the international spice industry, owing to its high medicinaland economic value. Consequently, the musk deer species are subjected to over-hunting,due to the huge demand of the market. Coupled with rapid economic development of humansociety, the ecologoical environment and habitat of the musk deer have been damaged andnarrowed seriously. For these reasons, the musk deer species are in steep declining andendangered. In order to well, more scientificlly, protect and make advantage of musk deerresources, artificially musk raising work has started in1958. Now, some achievements hasbeen made after many years of research and practice. However, there are still manyproblems to be solved, such as musk yield gene screening, hormores that affect musk yield,all of which have no breakthrough so far. Therefore, there are still problems to be solved,such as how to improve musk yield scientifically without affecting the natural population ofmusk deer and the normal physiological and reproductive regularity of musk deer.In this paper, association among polymorphisms of androgen receptor gene, the levelsof gonadal hormone and musk yield in Moschous Berezovskii has been studied, and someresults has been achieved as followed.1. An efficient method that used for extraction of genomic DNA from musk deer hairhas been founed. Two methods including PCR cycler method and the traditionalphenol/chloroform method were used to extract total DNA from musk deer hair.The exon1of androgen receptor in musk deer was amplified using the DNA as a template extracted bythe above methods, respectively. The results showed that PCR cycler method was betterthan the traditional phenol/chloroform method because the stripes of PCR production in gel were very clear. Only3-5hairs were needed by PCR cycler method, much less than thatneeded by traditional method when acquiring almost the same amout of DNA, and a higherpurity was also achieved(A260nm/A280nm=1.818). Because the PCR cycler method was moresimple and efficient than the traditional phenol/chloroform method, it is suitable to collecthair roots from unique conservation animals, intensive stress animals and difficultlyimmobilized large domestic animals. So the PCR cycler method to extract genomic DNAfrom hair deserves extensive application.2. The polymorphism of Exon1, Exon4and Exon8in AR gene of male Muschusberezorskii does not exist. PCR-SSCP was used to detect the polymorphism of Exon1,Exon4and Exon8in AR gene of male Muschus berezorskii (170individuals), and AR genewas sequenced. The results showed that polymorphism of Exon1, Exon4and Exon8in ARgene of male Muschus berezorskii does not exist. So Exon1, Exon4and Exon8in AR geneof male Muschus berezorskii was highly conserved.3. To detect the concentrations of gonadal hormones (testosterone, estradiol andprogesterone) and their association with musk yield during musk-secreting period (MSP) inmale Moschus berezovskii. The levels of gonadal hormones were detected in feces which werecollected from April,2010to December,2011in male Moschus berezovskii usingradioimmunoassay (RIA) method. The result showed that the testosterone and estradiol levelsof individuals at the various ages had a obvious tendency in the MSP. The concentrations oftestosterone were very low in normal period (NP), gradually increased in beforemusk-secreting period (BMSP), rapidly increased in prime musk-secreting period (PMSP),which had significant difference with that of NP (P＜0.05), and peaked in vigorousmusk-secreting period (VMSP), which was significant higher than that of other periods (P＜0.05), respectively, then rapidly dropped in later musk-secreting period (LMSP) andcontinually descended in after musk-secreting period (AMSP). The concentrations of estradiolhad a similar pattern with that of testosterone. The concentration of estradiol peaked in VMSP,which was significant higher than that of other periods (P＜0.05) except that eight totwelve-year-old male Moschus berezovskii had not significant difference with that of LMSP.No obvious tendency was detected in progesterone level during musk-secreting period in maleMoschus berezovskii. The variation of the levels of testosterone of the male musk deer duringthe same period at different ages was explained as follows: in NP of male musk deer, there is no significant differences at each stage of musk-secreting period; the level of testosterone ofthe1year male musk deer had significant difference with2-7years group(P＜0.05)duringBMSP, BMSP and VMSP; the level of testosterone of the1year male musk deer does notshow significant difference with8-10years in VMSP, while the level of testosterone of the1year male musk deer exist significant difference with2-7years group and8-10years group atthe late stage of musk-secreting period(P＜0.05); all other periods the differences dispalyedsignificant difference (P＜0.05).The levels of estradiol of the male musk deer during thesame period at different ages was explained as follows: the level of estradiol of the1yearmale musk deer had significant difference with2-7years,8-10years old male musk deer inthe NP and the PMSP (P <0.05). The level of estradiol of1year male musk deer s hadsignificant difference (P <0.05) with8-10-year-old male musk deer in LMSP, during all otherperiods the differences were not significant. Association analysis demonstrated that there wasa strong and significant positive association (R~2=0.6504,P＜0.05)between the testosteronelevels and musk yield. While the estradiol levels and musk yield had a significant positiveassociation (R~2=0.4565,P＜0.05). Finally it can be seen that not only had testosterone effecton musk yield, but also other hormones, such as estradiol. So those findings will provide notonly new ideas and ways for research work on Moschus berezovskii, but also scientific basisfor enhancement of musk yield by exogenetic hormones.It is an ideal way to study the gonadal hormones in semi-domestication wild animals byfeces samples. This study has important academic and economic value and will contribute alot to the protection and exploitation of musk that is endangered.