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Mineralization ages of many mineral deposit types (such as orogenic Au, stratabound Cu, and Mississippi Valley-type Pb-Zn deposits) are still difficult to date by the traditional isotopic chronometry because of the lack of suitable minerals. We have made efforts to establish a widely suitable dating technique to determine ore formation ages using a high-precision 40Ar/39Ar method on ubiquitously present fluid inclusions in quartz, sphalerite, and other nonpotassium minerals from hydrothermal deposits. The Xitian W-Sn polymetallic deposit in central South China contains several minerals suitable for isotopic dating for interchronometer comparison. 40Ar/39Ar laser step heating of 16 micas from ore veins, greisen, and metallogenic granites yields flat age spectra and thus well-defined ore formation ages ranging from 152.4 ± 1.5 (2σ) to 148.1 ± 1.4 Ma with an average of 150.2 ± 0.6 Ma. 40Ar/39Ar progressive crushing of nine quartz samples produces well-defined isochron lines for their primary fluid inclusions corresponding to isochron ages of 153.7–149.9 Ma with an average of 151.6 ± 0.6 Ma. Cassiterites from three hand specimens have weighted mean 206Pb/238U ages of 151.5 ± 1.7 (2σ), 149.7 ± 2.1, and 151.7 ± 2.1 Ma. All these new geochronological dates and previous molybdenite Re-Os ages yield well-constrained mineralization ages of 153–148 Ma for the Xitian W-Sn polymetallic deposit, which also confirms conclusively that the quartz 40Ar/39Ar progressive crushing technique is a feasible, valid dating technique. Furthermore, significant age information on the secondary fluid inclusions is potentially obtained simultaneously by this technique. We expect that this novel dating technique will be widely applied to determine the geologic fluids trapped in minerals during hydrothermal mineralization, hydrocarbon accumulation, metamorphism, tectonic activities, and other geologic processes.

Hydrothermal fluid activity associated with geological processes can now be dated by 40Ar/39Ar progressive crushing of minerals thanks to recent advances in high precision mass spectrometry. However, methods of data analysis and interpretation for these high-resolution measurements still need to be refined. In this study, we report further insights into using K-Cl-Ar diagrams as tools for interpreting ages of secondary and primary fluids from 40Ar/39Ar stepwise crushing experiments. Three paragenetic mineral pairs of muscovite and wolframites from a southern China tungsten deposit were investigated using the 40Ar/39Ar technique through laser incremental heating and progressive crushing of single minerals. Incremental heating analyses of muscovites yielded flat age spectra defining plateau ages of 156–153 Ma. Progressive crushing experiments of wolframites yielded anomalously old apparent ages due to excess 40Ar. However, the apparent ages decline quickly after the initial steps and stabilize to form age plateaus of 156–153 Ma without excess 40Ar. The plateau age steps interpreted as ages of gases derived from primary fluid inclusions (PFIs), yield well-defined isochrons with ages ranging from 157 to 153 Ma and initial 40Ar/36Ar values that are indistinguishable from the modern atmospheric value. Digitally created 2D- and 3D-diagrams of K–Cl–Ar correlations can easily reveal distribution trends and correlation planes from the crushing steps. Interpretations of these diagrams further reveal the ages of secondary fluid inclusions (SFIs) (87 to 83 Ma) and primary fluid inclusions (PFIs) (159 to 150 Ma). Raw data from SFIs degassed during the initial crushing steps form scatters on inverse isochron plots. However, 2D and 3D K-Cl-Ar diagrams yield SFI ages that agree with 40Ar/39Ar ages of K-feldspar veins cutting the tungsten ore bodies.

Coesite- and microdiamond- bearing ultra-high pressure (UHP) eclogites in the North Qinling terrane have been widely retrogressed to amphibolites. Previous geochronological studies on these UHP rocks mainly focused on the timing of peak eclogite facies metamorphism. The Kanfenggou UHP metamorphic domain is one of the best-preserved coesite-bearing eclogite occurrences in the North Qinling terrane. In this study, mafic amphibolites and host schists from this domain were collected for 40Ar/39Ar dating to constrain their retrograde evolution. Two generations of amphibole are recognized based on their mineral parageneses and 40Ar/39Ar ages. A first generation of amphibole from garnet amphibolites yielded irregularly-shaped age spectra with anomalously old apparent ages. Isochron ages of 484–473 Ma and initial 40Ar/36Ar ratios of 3695–774 are obtained from this generation of amphibole, indicating incorporation of excess argon. Second generation amphibole occurs in epidote amphibolites yielded flat age spectra with plateau ages of 464–462 Ma without evidence for excess argon. These ages suggest that the amphibolite-facies metamorphism has taken place as early as 484 Ma and lasted until 462 Ma for the North Qinling UHP metamorphic rocks. Phengite from the country-rock schists yielded 40Ar/39Ar plateau ages of 426–396 Ma, with higher phengite Si contents associated with the older the plateau ages. Based on our new 40Ar/39Ar ages and previous zircon U[sbnd]Pb geochronological data, we construct a new detailed pressure-temperature-time (P-T-t) path illustrating the retrograde metamorphism and exhumation rate of the North Qinling eclogites and host schists. The P-T-t path suggests that these UHP metamorphic rocks experienced initial medium-to-high exhumation rates (ca. 8.7 mm/yr) during the Early Ordovician (489–484 Ma), which was mainly derived from buoyancy forces. Subsequently, the exhumation rate decreased gradually from ~0.8 to 0.3 mm/yr from 484 to 426 Ma, which was probably governed by extension and/or erosion.

The Jinchang gold deposit has been extensively studied, but precise dates for its formation are debated. Native gold mainly occurs as inclusions within pyrite and quartz. In this study, we analysed quartz crystals coeval with gold precipitation from two different types of mineralization using the ArgusVI multi-collector noble gas mass spectrometer by the stepwise crushing technique to resolve the timing and genesis of gold mineralization. 40Ar/39Ar dating of quartz samples (J12Q) from breccia ore yields a plateau age of 109.87 ± 0.86 Ma, and an inverse isochron age of 109.87 ± 0.88 Ma. Quartz samples (J18Q) from vein ore yields a slightly younger plateau age of 107.76 ± 0.85 Ma, with an inverse isochron age of 107.76 ± 0.92 Ma. These dates place the ore-forming age of the Jinchang gold deposit at 107~110 Ma, much younger than previously published radiometric ages, suggesting the gold mineralization is spatio-temporally associated with the granite porphyry. The formation of the Jinchang gold deposit is consistent with the regional late Mesozoic porphyry-epithermal gold mineralization event in the Yanbian-Dongning area. Finally, our study shows that 40Ar/39Ar of quartz can be used as a powerful tool to date the formation ages of hydrothermal ore deposits.

First comprehensive investigations of the Cuonadong leucogranite exposed in North Himalayan gneiss dome of southern Tibet are presented in this study. The SIMS U–Pb ages of oscillatory zircon rims scatter in a wide range from 34.1 to 16.0 Ma, and the Cuonadong leucogranite probably emplaced at 16.0 Ma. High-precision 40Ar/39Ar dating on a muscovite sample yields an essentially flat age spectrum with consistent plateau and isochron ages, indicating that the Cuonadong leucogranite cooled below 450 °C at 14 Ma. Based on the youngest zircon U–Pb age and muscovite 40Ar/39Ar age, the Cuonadong leucogranite experienced rapid cooling with a rate of 119 °C/Myr from 16 to 14 Ma. The geochronological data of this undeformed leucogranite also suggest that the ductile extension of the South Tibetan Detachment System in the eastern Himalaya ceased by ca. 14 Ma. Furthermore, the initial Sr–Nd isotopic compositions and Nd model ages demonstrate that the leucogranite was derived from metapelitic source within the Greater Himalayan Crystalline Complex. The distinct Ba depletion with high Rb/Sr ratios and negative Eu anomalies make it clear that the leucogranite melts were generated by breakdown of muscovite under fluid-absent conditions.

Increasingly more data have indicated that the 40Ar/39Ar crushing technique provides a very useful approach to determine the mineralization ages of hydrothermal ore deposits. In this study novel gas mixing lines are proposed based on the data of two quartz samples by 40Ar/39Ar crushing. Electron microprobe analyses indicate that the quartz grains contain K-rich silicate microlites. Both quartzs by crushing yield two mixing lines with ages corresponding respectively to those of K-feldspar or sericite (post-mineralization fluids) and muscovite samples (ore-forming fluids). This is the first report that both ages of secondary and primary fluid inclusions (SFIs and PFIs) are confirmed correspondingly by those of the K-rich minerals. This study strongly indicates that the 40Ar/39Ar crushing technique is very useful to determine the ages of geofluid activities. The newly proposed gas mixing patterns are shown on the inverse and normal isochron diagrams, indicating: (1) the mixtures are in different proportions of the PFIs and SFIs in different crushing steps; (2) the gas mixing lines yield PFI ages with low initial 40Ar/36Ar ratios; (3) an intermediate age between PFI and SFI ages cannot be obtained because the progressive crushing technique never release gas mixtures with a constant PFI/SFI proportion for each step. The gas mixing lines are thus interpreted to yield significant geological ages. The mixing patterns will help us better understand the 40Ar/39Ar dating results and be used for references to other isotopic mixing isochron systems.

The joint methods of 40Ar/39Ar laser stepwise heating and in vacuo crushing have been applied to date amphiboles from the North Qaidam ultra-high pressure metamorphic amphibolites. Two amphibole samples analyzed by laser heating yielded saddle-shaped age spectra with total gas ages of 574.5±2.5 and 562.5±2.5 Ma. These ages are much older than the reported zircon U-Pb ages (∼495 Ma) from Yuka eclogite, indicating the presence of excess 40Ar. In order to decipher the occurrence of excess 40Ar and constrain the age of amphibolite-facies retrogression, two duplicate amphibole samples were further employed for 40Ar/39Ar in vacuo crushing analyses. Both samples exhibit similar monotonically declining release spectra, which are characterized by rapid decline of anomalously old apparent ages in the early steps. The data of the late steps yielded concordant apparent ages with plateau ages of 460.9±1.2 and 459.6±1.8 Ma. We interpret that gases released in the early steps derive from the significant excess 40Ar containing secondary fluid inclusions (SFIs) due to their distribution characteristics along cracks leading to be easily extracted, whereas those released in the later steps represent the contribution of the small primary fluid inclusions (PFIs).

A new fully automatic 40Ar/39Ar laboratory with a Thermo Scientific© ARGUS VI mass spectrometer has been established in China University of Geosciences (Wuhan). We designed and developed a mini efficient preparation system (80 mL), a CO2 laser for heating samples, a crusher for extracting fluid inclusions within K-poor minerals and an air reservoir (31 L) and pipette (0.1 mL) system. The ARGUS VI mass spectrometer is operated by the Qtegra Noble Gas software, which can control the peripheral accessories, such as pneumatic valves, CO2 laser and crusher through a PeriCon (peripheral controller). The experimental procedures of atmospheric argon analyses, 40Ar/39Ar dating by laser stepwise heating and by progressive crushing in vacuo, can be fully automatically performed. The weighted mean of atmospheric 40Ar/36Ar ratios is 302.22±0.03 (1σ, MSWD=0.74, n=200), indicating that air reservoir and pipette system and the whole instrument system are very stable. This laboratory is a successful pioneer example in China to establish a new noble gas laboratory with self-made peripheral accessories expect for the mass spectrometer.

The West Qinling orogen in central China contains several dozens of gold deposits. However, absolute ages of gold mineralization and its relations to regional tectonism, magmatism, and metamorphism remain not tightly constrained for most of these gold deposits. Here we integrate 40Ar/39Ar dating of sericite from various hydrothermal alteration assemblages and U-Pb dating of zircon grains from magmatic rocks within and surrounding the Liziyuan gold deposit in the northern belt of the West Qinling orogen to provide new insights into the age and tectonic setting of gold mineralization. The Liziyuan gold deposit consists of six ore camps (Yuzigou, Liushagou, Jiancaowan, Kuangou, Suishizi, and Yingfang) that are hosted in Ordovician greenschist facies metamorphosed sedimentary-volcanic rocks and, less significantly, the Middle Triassic Tianzishan monzogranite pluton intruding the metamorphic rocks. Gold mineralization consists of auriferous quartz-pyrite veins and subordinate sulfide disseminations in hydrothermally altered wall rocks, with minor calcite-polymetallic sulfide veins in the monzogranite-hosted orebodies. Ore-related alteration assemblages are dominated by quartz, sericite, pyrite, chlorite, and calcite, with gold occurring mostly as native gold grains enclosed in or filling microfractures of pyrite and quartz. Barren alteration assemblages, dominated by K-feldspar, quartz, sericite, and pyrite, are locally developed along eastern margin of the Tianzishan monzogranite. Two sericite aggregates extracted from gold ores in the Liushagou camp yield well-defined 40Ar/39Ar plateau ages of 200.1 ± 1.2 and 198.8 ± 1.1 Ma (2σ), whereas those from barren alteration assemblages in the Tianzishan monzogranite, which hosts the Suishizi ore camp, give rise to older 40Ar/39Ar plateau ages of 211.9 ± 1.2 and 211.3 ± 1.3 Ma (2σ). The Tianzishan monzogranite pluton and several dioritic to granitic stocks and dykes in and surrounding the gold mines have zircon U-Pb ages ranging from 241.3 ± 1.2 to 212.4 ± 0.9 Ma (2σ). These new isotopic ages suggest that the Liziyuan gold deposit formed at the Triassic-Jurassic boundary, arguably representing the youngest orogenic-type gold mineralization event over the northern belt of the West Qinling orogen. Gold mineralization postdates magmatism in the Liziyuan gold deposit at least by about 10 million years, precluding a possible genetic relation between the two. Rather, the ore genesis was likely related to metamorphic fluids released from Paleozoic sedimentary and volcanic rocks in relation to the Qinling orogenesis. In contrast, the barren hydrothermal alteration assemblages were likely caused by fluids exsolved from a magma presumably represented by the ca. 212 Ma diorite dyke. Results presented here, when combined with independent geological and geochemical data, suggest that the Liziyuan gold deposit formed most likely under a post-collisional extensional setting related to the West Qinling orogeny.

The Qinzhou Bay–Hangzhou Bay metallogenic belt (QHMB), South China, contains numerous variable deposits, including Au, Cu, Pb, Zn, Ag, W, Sn, U-polymetallic ore deposits. The Tianjingshan gold deposit is located in the northern segment of the QHMB and is a typical large-scale lode gold deposit. Auriferous quartz veins occur along the contact zones between the Neoproterozoic greenschist-facies metamorphic rocks and gneissic granite and are structurally controlled by brittle faults. Mineralization-related hydrothermal alteration mainly includes silicification, pyritization, sericitization, and chloritization. Four stages of alteration and mineralization are recognized: quartz (I), quartz–pyrite (II), quartz–polymetallic sulfide (III), and quartz–carbonate–fluorite (IV) stages. Gold mineralization occurs mainly in stages II and III, as visible gold. Sericite that formed in association with mineralization stages II and III has well-defined step heating plateau 40Ar/39Ar ages of 243.4 ± 2.3 and 239.5 ± 2.3 Ma, respectively, suggesting that the gold mineralization took place during the Middle Triassic, consistent with the timing of the regional Indosinian intra-continental orogeny. In contrast, the Hanjia gneissic granite and Mi’ao monzogranite in the Tianjingshan deposit have zircon U–Pb ages of 789 ± 7 and 147 ± 2 Ma, respectively, which indicates that both intrusions were not involved directly in the gold mineralization. δ18O and δD values from fluid inclusions of auriferous quartz range from −1.1 to +2.6‰ and from −76.4 to −62.8‰, respectively, suggesting that the mineralizing fluid was likely of metamorphic origin. Gold-bearing sulfide minerals have δ34S values ranging from +0.6 to +9.8‰ with a mean of +7.1‰, which are similar to δ34S values of Neoproterozoic greenschist-facies metamorphic rocks and of typical orogenic gold deposits; therefore, we suggest that sulfur is derived mainly from regional metamorphic country rocks. The above mentioned characteristics, together with geological features, suggest that Tianjingshan is a typical orogenic Au deposit that formed during the Indosinian orogeny. Combined with knowledge of other similar deposits, the age and characteristics of the Tianjingshan gold deposit imply that Middle Triassic orogenic gold deposits in the QHMB could be common and of high economic potential.

Cerium is one of multivalent rear earth elements, which can transfer from trivalence to tretavalence at oxidizing environment. This process may cause variable degrees of fractionation of Ce from other trivalent rear earth elements, and thus may provide specific insight into the geological processes associated with marked redoxomorphism. Multiple geochemical tracing of Sr-Nd-Ce isotopes are performed on the felsic and mafic intrusives of the Neoproterozoic (~800 Ma) Huangling complex located at the eastern Three Gorges, South China. The intrusive rocks exclusively show various extents of negative Ce anomalies. On the e Ce-e Nd plot, most samples from the mafic intrusions scatter within the second quadrant, whereas those from the felsic intrusions within the fourth Quadrant. Both of the two groups exhibit relatively large range of e Ce(t) variation but limited e Nd(t) range, which cause a deviation from the “crustal array” and reveal a decoupled Nd-Ce isotope correlation. The intermediate-felsic suite have varied Ce/Ce* ratios but broadly proximate e Ce(t) values, indicating that their negative Ce anomalies were generated during the magmatism; on the contrary, a positive correlation between e Ce(t) and Ce/Ce* is observed for the intermediate-mafic suite, an indication of an origin of post-magmatic alteration or metamorphism for their Ce anomalies. Calculation of model age, the occurrence age of negative Ce anomalies (T Ce) for the intermediate-mafic samples infers that the alteration events took place >350 Ma. Data showed that negative Ce anomalies of the felsic intrusions may reflect an increase of oxygen fugacity during magma ascending, rather than an inheritance from their source rocks. This explanation implies that the Neoproterozoic magmatism occurred at the continental nucleus of the Yangtze block were developing at a geodynamic context of rapidly regional uplifting.

Chrome chlorites are usually found as secondary phases formed by hydrothermal alteration of chromite deposits and associated mafic/ultramafic rocks. Here, we report the 40Ar/39Ar age of chrome chlorites separated from the Luobusa massive chromitites which have undergone secondary alteration by CO2-rich hydrothermal fluids. The dating results reveal that the intermediate heating steps (from 4 to 10) of sample L7 generate an age plateau of 29.88 &plusmn, 0.42 Ma (MSWD = 0.12, plateau 39Ar = 74.6%), and the plateau data points define a concordant inverse isochron age of 30.15 &plusmn, 1.05 Ma (MSWD = 0.08, initial 40Ar/36Ar = 295.8 &plusmn, 9.7). The Ar release pattern shows no evidence of later degassing or inherited radiogenic component indicated by an atmospheric intercept, thus representing the age of the hydrothermal activity. Based on the agreement of this hydrothermal age with the ~30 Ma adakitic plutons exposed in nearby regions (the Zedong area, tens of kilometers west Luobusa) and the extensive late Oligocene plutonism distributed along the southeastern Gangdese magmatic belt, it is suggested that the hydrothermal fluids are likely related to the ~30 Ma magmatism. The hydrothermal fluid circulation could be launched either by remote plutons (such as the Sangri granodiorite, the nearest ~30 Ma pluton west Luobusa) or by a similar coeval pluton in the local Luobusa area (inferred, not found or reported so far). Our results provide important clues for when the listwanites in Luobusa were formed.

Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal noble gas preparation systems can clean up most geological samples. However, authigenic minerals from sedimentary rocks in oil/gas fields contain organic matter, which cannot be cleaned up by the normal preparation systems and thus influence the noble gas analyses. We introduce a novel gas purification system (PRC patent No. ZL201320117751.2), which includes several reversible purification pumps with different absorbing and degassing temperatures. It can well clean up water steam, carbon dioxide and organic gases. Mica minerals are often used for 40Ar/39Ar dating. A muscovite sample (2082MS) which could not be cleaned up by the normal preparation system with two SAES NP10® getters, becomes the test sample for a comparative experiment in this study. The experiment is assigned into 4 sections with the organic gas removal system (OGRS) “Closed/Opened” in turn. When the OGRS is closed only with two NP10 getters for purification, the 40Ar intensities increase in curves with inlet time because of impurities, the 40Ar/39Ar dating results yield age errors about ± 2%– ± 1% (2 σ ) . When the OGRS is opened for purification, in contrast, the 40Ar intensities decrease linearly with inlet time. This indicates that the gases have been cleaned up effectively, and the 40Ar/39Ar results yield ages with errors in ± 0.4%. The OGRS is very helpful to obtain high-quality analysis data.

Dating ore minerals is the most direct method to determine the mineralization age of a deposit, but only a few ore minerals can be directly dated by traditional isotopic geochronometers. The aim of this study is to investigate the possibility of direct dating of the ore minerals cassiterite and wolframite from the Piaotang tungsten deposit using the 40Ar/39Ar stepwise crushing technique, comparing the age to coexisting K-rich muscovite dated by 40Ar/39Ar laser stepwise heating. The cassiterite, wolframite and muscovite samples were separated from four pieces of ore hand-specimens. The 40Ar/39Ar isochron ages of cassiterite and wolframite are concordant with ages of their coexisting muscovite, indicating that cassiterite and wolframite are suitable ore minerals for directly dating the ore-forming event by 40Ar/39Ar stepwise crushing.

The aim of this study is to investigate the possibility of dating fluid inclusions in cassiterite using the 40Ar/39Ar technique by crushing in vacuo . Paragenous muscovite and cassiterite in a piece of tungsten ore from the Piaotang tungsten deposit in southern Jiangxi Province were selected. Laser stepwise heating of the muscovite yields a flat age spectrum with a plateau age of 159.3±1.5 Ma. The 40Ar/39Ar dating result of cassiterite by crushing forms a declining age spectrum marked by the highest apparent age of 3954 Ma at the 1st stage, then shows an apparent decline step-by-step, and finally a plateau appears with a plateau age of 159.1±1.8 Ma in the last 12 stages (from 7 to 18, or about 83% of the total 39Ar). The data points of cassiterite clearly distribute into two groups corresponding to secondary and primary fluid inclusions, and their mixtures. The secondary ones contain excess 40Ar and their data points scatter on the inverse isochron diagram of 36Ar/40Ar vs. 39Ar/40Ar, while the primary ones do not contain excess 40Ar and their data points yield an excellent isochron line corresponding to an age of 158.6±2.9 Ma. The 40Ar/39Ar isochron age of the cassiterite by crushing is well concordant with the age of the paragenous muscovite by 40Ar/39Ar stepwise heating, indicating that mineralization occurred at 159 Ma. This study reveals that cassiterite is a suitable dating target for 40Ar/39Ar stepwise crushing. Moreover, the isochron age of the primary inclusions represent the mineralization age of the Piaotang tungsten deposit.

Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis (BSA) in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions (SCAR) marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex (MHC) class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference (p

To observe and assess the cognitive changes of mild cognitive impairment (MCI) in the elderly.A cohort study design was conducted among 47 patients with MCI and 21 control selected from the same convalescent camp, Montreal cognitive assessment (MoCA), mini mental state examination (MMSE) and clock drawing test (CDT) were performed to all subjects at the onset of study and 12 months later.The score of MMSE, CDT, MoCA and its subitems including visuospatial skill and delayed recall of MCI group were lower than the baseline after 12 months, with significantly decline in the score of MoCA (P = 0.041) and delay recall (P = 0.003). There was no obvious difference in the score of control between the baseline and that after 12 months.The decline of delayed recall occurred early and significantly, which may be a predictor in the conversion of mild cognitive impairment to dementia.

Using single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing, single nucleotide polymorphisms (SNPs) of growth hormone receptor (GHR) gene were detected in an arctic fox population. Correlation analysis between GHR polymorphisms and growth traits were carried out using the appropriate model. Four SNPs, G3A in the 5'UTR, C99T in the first exon, T59C and G65A in the fifth exon were identified on the arctic fox GHR gene. The G3A and C99T polymorphisms of GHR were associated with female fox body weight (Pamp;0.05) and the T59C and G65A polymorphisms of GHR were associated with male fox body weight (Pamp;0.05) and the skin length of the female fox (Pamp;0.01). Therefore, marker assistant selection on body weight and skin length of arctic foxes using these SNPs can be applied to get big and high quality arctic foxes.

The SNPs in partial coding sequence of MC3R and MC4R genes were identified by polymerase chain reaction followed by single strand conformation polymorphism (PCR-SSCP) analysis and DNA sequencing in shack-Kee and Columba domestica from Harbin area. Correlation analysis between MC3R and MC4R polymorphism and growth and body composition traits was carried by the least square analysis. The genotypes of T91G mutation in MC3R gene and A903G mutation in MC4R gene proved to have significant association with body weight, carcass weight, and holo-carcass weight in shack-Kee (P0.05). The interaction of MC3R-T91G and MC4R-A903G was discussed through combination genotype analysis. The least square analysis showed that the combined genotype had significant association with holo-carcass weight (P0.05). Multiple comparisons revealed that BBAA genotype birds had a higher holo-carcass weight than AABB genotype birds and BBAA genotype was the beneficial genotype for the growth of body weight.

To investigate the relationship between the susceptibility to cirrhosis and the single nucleotide polymorphisms (SNPs) at C-1350T and G-944C loci of class II transactivator (CIITA) gene promoter IV in chronic HBV carriers.C-1350T and G-944C loci of CIITA gene promoter IV were analyzed by sequence-specific primer PCR (PCR-SSP) in 544 chronic HBV carriers and 125 non-HBV infected healthy blood donors.Among the chronic viral hepatitis B patients, there were significantly decreased frequencies of CC and TG haplotypes, and significantly increased frequency of CG haplotype among patients with liver cirrhosis (CG vs. CC: chi2=8.274, df=1, P0.01; CG vs. TG: chi2 = 15.027, df =1, P0.01). There were no significant differences in the frequencies of CC and TG haplotypes between chronic hepatitis B and liver cirrhosis patients (chi2 = 1.231, df =1, P0.05). There were significantly increased frequencies of CC/CC (Group 1) genotype and genotypes contained CG haplotype (Group 3), and significantly decreased frequencies chi2= 7.176, df = 1, P0.01; Group1 vs Group 4, chi2 = 19.818, df = 1, P0.01; Group 3 vs Group 2, chi2 = 11.423, df = 1, P0.01; Group 3 vs Group 4, chi2 = 34.226, df = 1, P0.01; Group 1 vs Group 3, chi2 = 0.009, df = 1; Group 2 vs Group 4, chi2 = 2.176, df = 1).Polymorphisms at -1350 and -944 loci of CIITA gene promoter IV are associated with susceptibility to liver cirrhosis in chronic HBV carriers. The chronic HBV carriers bearing CC/CC genotype or genotypes containing CG haplotype progress into liver cirrhosis with more probability.

To construct eukaryotic expression vectors containing three different haplotype cDNAs of human CIITA gene.cDNA fragments of three different CIITA haplotypes were obtained by inducing one or two single nucleotide mutations of wild type recombinant plasmid EBS-NPL-CIITA cDNA, which correspond to two non-homonymy single nucleotide polymorphism (SNP) sites in the coding region of human CIITA gene, using overlap extension PCR site-directed mutagenesis technology. The above-mentioned three haplotype cDNAs were respectively cloned to EBS-NPL-CIITA linearized vectors. Positive clones were identified by colonial PCR and restriction endonuclease digestion and were sent to be sequenced. Then eukaryotic expression vectors containing four different haplotypes and an empty vector EBS-NPL were transfected into HepG2 cells respectively. HLA-DR was detected by indirect cell immunofluorescence technique.The cDNA fragments of three different human CIITA haplotypes were successfully constructed, and the eukaryotic expression vectors containing three different haplotype cDNAs of human CIITA gene were obtained. No expression of HLA-DR was observed in the original HepG2 cells and empty vector transfected HepG2 cells and the expression of HLA-DR emerged in the HepG2 cells transfected with four eukaryotic expression vectors.The eukaryotic expression vectors containing three different haplotype cDNAs of human CIITA gene were successfully constructed, and they are essential for our further study of the functional differences of them.

SSR fingerprints were analyzed in three generations of fat line (FL) and lean line (LL) of broiler chickens. Changes in gene frequencies of every locus were evaluated. Thus the relationship between SSR markers and VLDL (a trait representing fat mass of broiler), which is the basis for early selection of LL broiler, was examined. Fourteen microsatellite locus were successfully amplified with 4 of 5 primers used. The results of chi2 test for the gene frequencies of every locus show that one locus was significantly different in generation 1(P0.05), two in generation 2 and 4 in generation 3.