波尔山羊杂交后代及其亲本随机扩增多态DNA研究

利用随机扩增多态DNA技术研究了波尔山羊、唐山奶山羊、青龙本地山羊以及波尔山羊与这两个山羊群体杂交后代共计128个山羊个体的随机扩增多态DNA。结果表明：（1）总群体平均遗传多样性指数（Hsp）为0.6974,群体遗传分化指数为0.9706,山羊群体间平均遗传距离指数（0.1314～0.2052）明显大于群体内的相应值（0.0582～0.1440）,上述结果说明,所研究山羊群体不仅具有较为丰富的遗传多样性,而且其核基因组遗传变异主要存在于群体间。（2）山羊群体间的分子聚类关系与各群体间的亲缘关系基本一致。 Abstract:The random amplified polymorphic DNA（RAPD）of 128 individuals was studied,which were from Boer goat, Tangshan dairy goat,Qinglong native goat and their hybrids crossbred with Boer goat.The average index of genetic polymorphism for whole population（Hsp）and the index of genetic differentiation were 0.6974 and 0.9706,respectively.The average index of genetic distance between populations（0.1314～0.2052）was significantly higher than that within populations（0.0582～0.1440）.All of these indicated that the genetic polymorphism was not only abundant,but also the genetic variation was mainly existed between goat populations.The molecular dendrogram among goat populations was in accord with their genetic relationship.     

波尔山羊头颈部毛色特征以及黑色蹄色的遗传方式

通过实际观察、考察育种记录、遗传分析和适合性检验,分析了秦皇岛市波尔山羊繁育改良研究中心波尔山羊以及波尔山羊与唐山奶山羊级进杂交改良后代的头颈部毛色特征及蹄色特征的遗传方式。结果表明,波尔山羊头颈部毛色特征以及黑色蹄两个性状均分别由两个连锁在同一条常染色体上的隐性基因控制,二者间为不完全连锁遗传,其遗传距离为7.5个遗传单位。 Inheritance of Head and Neck Colour and Black Hoof of Boer Goat LI Xiang-long,GONG Yuan-fang,LIU Zheng-zhu,HAN Xiu-li Department of Animal Science,Hebei Vocation-techenic Teachers College,Changli hebei,066600,China Abstract:The inheritance of head and neck color and black hoof of Boer goats and their offspring were analyzed by observing,breeding data and statistic test in the Crossbreeding and Improving Research Center of Boer goat in Qinhuangdao city.The results indicated that the color of head and neck and black hoof of Boer goat were all controlled respectively by two linked recessive genes on one autosome.The rate of crossing-over between the genes of head and neck color and black hoof was 7.5 genetic units. Key words:boer goat; color of head and neck; black hoof; inheritance     

乌羊和小香羊的RAPD分析

用40条多态引物对乌羊、小香羊、南江黄羊、黑山羊、川东白山羊、波尔山羊和马头山羊7个品种(或群体)进行RAPD分析,其中28条引物扩增出多态性谱带,并用于进一步对12只乌羊个体和12只小香羊个体基因组进行扩增.扩增产物以1.5%琼脂糖凝胶(含0.5μg/ml溴化乙锭)电泳分离.Nei氏公式计算品种间的遗传距离指数和品种内的遗传相似指数,NJ法构建系统聚类图.结果表明:乌羊和川东白山羊间的遗传距离最小,亲缘关系较近,而小香羊与各品种间的遗传距离都较大,亲缘关系较远.乌羊群体及小香羊品种都具有一定的遗传稳定性。 Abstract:A total of 40 primers generated polymorphic loci were used in random amplified polymorphism DNA(RAPD)analysis in seven goat breeds(or populations)including Wu goat,Small-Xiang goat,Nanjiang Brown goat,Black goat,Chuandong white goat,Boer goat,Matou goat.28 of them were selected for further amplification in individuals of 12 Wu goats and 12 Small-Xiang goats because of their different amplified patterns among seven goat breeds.Amplification products were separated by 1.5% agarose gel(contain 0.5μg/ml ethidium bromide)electrophoresis.Genetic distance indexes among breeds and genetic similarity indexes within breed were calculated by Nei,and the phylogenetic tree was constructed by NJ method.The results indicate that the genetic distance index between Wu goat population and Chuandong white goat breed is smallest,therefore Wu goat population is closely related to Chuandong white goat breed.While the genetic distance indexes between Small-Xiang goat breed and any other goat breeds are all big,so Small-Xiang goat breed is far related to any other goat breeds.The results also indicate that the genetic stability either among the Wu goat population or the Small-Xiang goat breed reaches some extent.     

波尔山羊及其杂交改良后代群体遗传结构与亲缘关系研究

利用RAPD标记和POPGENE、PHYLIP及SPSS等统计分析软件,研究了波尔山羊及其杂交改良后代群体的遗传结构及遗传亲缘关系。结果表明,波尔山羊与其杂交改良后代间特别是高代杂种间具有相似的多态基因座百分率、等位基因数和基因多样性。随着级进杂交改良代数的递增,高代杂种之间以及与改良亲本之间的群体遗传结构的差异逐渐缩小,群体间的基因分化降低,基因流动和遗传相似度增加,遗传距离缩小,高代杂种与波尔山羊间具有更近的遗传亲缘关系。 Abstract:The genetic structure and relationship of Boer goat and its upgrading offspring to Tangshan Diary goat were studied using the RAPD marker and some statistical program,such as POPGENE,PHYLIP and SPSS.The results indicated that there were the similar percentage of polymorphic loci,observed and effective number of alleles,gene diversity between Boer goat and its upgrading offspring,especially higher upgrading offspring.With the increasing of upgrading,the difference of population structure decreased as well as the genetic distance and differentiation among higher upgrading offspring and their improving parental,but gene flow and genetic identity increased.There was a close genetic relationship between higher upgrading offspring and Boer goat.     

用4个微卫星标记分析7个绵羊群体之间的遗传关系

分析了4个微卫星基因座BM143、OarHH35、OarAE101、BMS2508在7个绵羊群体（小尾寒羊、湖羊、乌珠穆沁羊、萨福克羊、多赛特羊、夏洛来羊、多赛特公羊×小尾寒羊母羊F1代杂种羊）286只绵羊中的遗传多态性。结果表明,这4个微卫星标记在7个绵羊群体中的等位基因数分别为9、11、14和9,其多态信息含量/有效等位基因数/杂合度分别为0.7073/3.7231/0.7314、0.8267/6.4399/0.8447、0.5743/2.5178/0.6028、0.6172/3.0712/0.6744,其中OarHH35的遗传变异最大,OarAE101最小。7个绵羊群体中小尾寒羊的遗传变异最大,湖羊的最小。基于Nei氏DA距离和DS标准遗传距离,采用UPGMA方法构建了系统发生树。该发生树将中国地方品种（小尾寒羊、乌珠穆沁羊、湖羊）和法国的夏洛来羊归为一类,将F1杂种羊、英国品种（萨福克羊和多赛特羊）归为另一类。绵羊微卫星基因分型技术为检查品种（群体）之间的遗传关系提供了一个有用的工具。 Abstract：The genetic polymorphisms of four microsatellite loci BM143,OarHH35,OarAE101,and BMS2508 were analyzed in 286 sheep of seven sheep populations (Small Tail Han sheep, Hu sheep, Ujumqin sheep, Suffolk sheep, Dorset sheep, Charolais sheep, F1 of Dorset♂ × Small Tail Han sheep♀). The numbers of alleles for BM143,OarHH35,OarAE101,and BMS2508 are 9, 11, 14 and 9 in seven sheep populations, respectively. The polymorphism information content/number of effective alleles/ heterozygosity of BM143,OarHH35,OarAE101 and BMS2508 were 0.7073/3.7231/0.7314, 0.8267/6.4399/0.8447,0.5743/2.5178/0.6028,0.6172/3.0712/0.6744 in 286 sheep, respectively. The results revealed the greatest genetic variation at OarHH35 locus and the lowest at OarAE101, the greatest genetic variation in Small Tail Han sheep and the lowest in Hu sheep among seven sheep populations. In the unweighted pair group method with arithmetic mean (UPGMA) dendrograms based on Nei's DA distance and Nei's DS standard genetic distance, the Chinese native breeds (Small Tail Han sheep, Ujumqin sheep, Hu sheep) were grouped together, then with Charolais sheep. The F1 crossbred sheep, and the two British native sheep (Suffolk sheep, Dorset sheep) also clustered together. Microsatellite genotyping in sheep provided a useful tool for examining the genetic relationships among breeds(populations).     

我国主要地方绵羊品种随机扩增多态DNA研究

对蒙古羊、湖羊、滩羊、小尾寒羊、乌珠穆沁羊、藏绵羊、阿勒泰羊7个地方绵羊品种和无角陶赛特羊、德国美利奴羊、萨福克羊3个引入品种基因组DNA进行了RAPD分析。结果表明：（1）RAPD可作为一种有效的标记用于绵羊品种之间遗传亲缘关系的分析。（2）在所使用的43种随机引物中,有35种引物扩增出多态谱带,多态频率为66.24%,说明RAPD技术用于研究绵羊核DNA的遗传变异具有较高的检出率和灵敏度。（3）总群体平均遗传多样性指数（HSP）为0.9139,说明绵羊群体具有较为丰富的遗传多样性。（4）我国地方绵羊品种间的分子聚类关系与其所处的地理位置、考古学结果,以及细胞遗传学研究结果基本一致,引入品种间的分子聚类关系也与其育成史基本一致。 Abstract:The genetic polymorphism and relationship of 7 indigenous sheep breeds of China and 3 imported sheep breeds were studied using random amplified polymorphic DNA (RAPD).The results indicated that the RAPD was an effective marker for the analysis of genetic relationship among sheep breeds.Among 43 arbitrary primers,35 were polymorphic.The percentage of polymorphic markers was 66.24%,which indicated that the RAPD had higher efficiency of polymorphism detection and sensitivity in studying the genetic variation among sheep breeds.The average index of genetic polymorphism for whole population (Hsp) was 0.9139,which showed that the genetic polymorphism was abundant between sheep populations.The genetic relationship between different indigenous sheep breeds in China was in accord with their localities,the results from archeology and cytogenetics and the genetic relationship between imported sheep breeds was in accord with their breeding history.     

不同猪种肠毒素大肠杆菌（ETEC）F4受体微卫星标记遗传差异性研究The

采用13号染色体上与K88ab和K88ac受体基因连锁的2对引物（S0223和S0068）,研究沙子岭猪和大约克猪的遗传差异性。结果表明,2个猪种在2个基因座均存在多态性,其基因杂合度和Shannon信息指数存在很大差异,而中外猪种的K88ab和K88ac受体基因也存在遗传差异,这2对引物可望作为K88ab和K88ac受体基因的遗传标记。Abstract: The genetic variation of ETEC F4 receptor in Shaziling and Yorkshire breeds were studied using two microsatellite markers(S0223 and S0068). The results showed that there were polymorphisms in the two markers, and there were great variations of the gene heterozygosity and Shannon information index in the two breeds. It was also reported that there were differences in K88ab and K88ac receptors in Chinese native breeds and foreign breeds, so the two markers might be the genetic markers of F4 receptor gene.     

三品系小型猪35个微卫星基因座的遗传学研究

利用35个微卫星基因座对中国三个品系的小型猪（贵州小型香猪、广西巴马小型猪、版纳小耳猪近交系）进行了遗传检测。计算出三个小型猪品系个体样本在35个微卫星基因座的纯合率,并对其进行t检验。计算出各品系的平均杂合度,多态信息含量（PIC）及品系间的遗传距离,并进行了系统聚类。结果表明三个品系的小型猪其基因纯合率均较高,其中版纳小耳猪近交系的基因纯合率最高;PIC和平均杂合度均较低;贵州小型香猪和广西巴马小型猪亲缘关系较近,并均与版纳小耳猪近交系的亲缘关系略远。 Abstract：The polymorphism of 35 microsatellites in the three miniature pig breeds in China(Guizhou miniature pig, Guangxi Bama miniature pig, Banna miniature pig inbred) was analysed. Rates of homozygote for 35 microsatellite loci in three miniature pig breeds were calculated,and t-test for them were performed. Mean heterozygosity and polymorphism information content(PIC) were calculated for all breeds, and genetic distances between these breeds were estimated. The dendrograms were obtained based on genetic distances. The results suggest that rates of homozygote in the three breeds are all high, and that is the highest in Banna miniature pig inbred. The results also suggest that polymorphism information content and mean heterozygosity in all the three breeds are low, and the genetic relationship between Guizhou miniature pig and Guangxi Bama miniature pig is closer than their relationship with Banna miniature pig inbred.     

Analysis of genetic diversity and phylogenetic relationships among red jungle fowls and Chinese domestic fowls

Genetic diversity and phylogenetic relationships among 568 individuals of two red jungle fowl subspe- cies (Gallus gallus spadiceus in China and Gallus gallus gallus in Thailand) and 14 Chinese domestic chicken breeds were evaluated with 29 microstaellite loci, the genetic variability within population and genetic differentiation among population were estimated, and then genetic diversity and phylogenetic relationships were analyzed among red jungle fowls and Chinese domestic fowls. A total of 286 alleles were detected in 16 population with 29 microsatellite markers and the average number of the alleles observed in 29 microsatellite loci was 9.86±6.36. The overall expected heterozygosity of all population was 0.6708±0.0251, and the number of population deviated from Hardy-Weinberg equilibrium per locus ranged from 0 to 7. In the whole population, the average of genetic differentiation among population, measured as FST value, was 16.7% (P<0.001), and all loci contributed significantly (P<0.001) to this differentiation. It can also be seen that the deficit of heterozygotes was very high (0.015) (P<0.01). Reynolds' distance values varied between 0.036 (Xiaoshan chicken-Luyuan chicken pair) and 0.330 (G. gallus gallus-Gushi chicken pair). The Nm value ranged from 0.533 (between G. gallus gallus and Gushi chicken) to 5.833 (between Xiaoshan chicken and Luyuan chicken). An unrooted consensus tree was constructed using the neighbour-joining method and the Reynolds' genetic distance. The heavy-body sized chicken breeds, Luyuan chicken, Xiaoshan chicken, Beijing Fatty chicken, Henan Game chicken, Huainan Partridge and Langshan chicken formed one branch, and it had a close genetic relationship between Xiaoshan chicken-Luyuan chicken pair and Chahua chicken-Tibetan chicken pair. Chahua chicken and Tibetan chicken had closer genetic relationship with these two subspecies of red jungle fowl than other domestic chicken breeds. G. gallus spadiceus showed closer phylogenetic relationship with Chinese domestic chicken breeds than G. gallus gallus. All 29 microstaellite loci in this study showed high levels of polymorphism and significant genetic differentiation was observed among two subspecies of red jungle fowl and 14 Chinese domestic chicken breeds. The evolutional dendrogram is as follows: evolutional breeds→primitive breeds (Chahua chicken and Tibetan)→red jungle fowl in China (G. gallus spadiceus)→red jungle fowl in Thailand (G. gallus gallus). The results supported the theory that the domestic fowls might originate from different subspecies of red jungle fowl and Chinese domestic fowls had independent origin.     

Classification of ecological types of the Chinese yak

To investigate the genetic resources and to clarify the classification status of the Chinese yak, the Maiwa yak, Jiulong yak, Datong yak, and Tianzhu White yak were intensively studied using microsatellite DNA, RAPD (random amplified polymorphic DNA), and AFLP (Amplified Fragment Length Polymorphism) DNA markers on the basis of the previous study work of the authors' on chromosomes and blood protein polymorphisms of the Chinese yak. The overall results showed that: (1) the genetic distance based on allele frequencies at the microsatellite loci between the Maiwa yak and Jiulong yak was the largest (1.506), and as expected, the two populations of the Maiwa yak had the smallest genetic distance (1.062). The four yak breeds were clustered into two groups: the first group comprised the Jiulong yak, and the second group comprised the remaining three breeds; (2) the genetic distance between the Datong yak and Tianzhu White yak was the smallest (0.0336), whereas the genetic distance between the Jiulong yak and Maiwa yak was the largest (0.0414) based on the data from the RAPD and RFLP analyses. The four yak breeds were again clustered into two groups with the Datong yak and Tianzhu White yak grouped together first, followed by the Maiwa yak; (3) analyses of the chromosomes and blood protein polymorphisms showed a similar pattern of relationship among the breeds. Therefore, it was concluded that the Chinese yak could be considered to be of two types with the Jiulong yak and Maiwa yak as their representatives, respectively. This conclusion was in accordance with the classification proposed later by professor Cai L and his colleagues, according to which the Chinese yak was classified into two types, the ‘Qinghai-Tibetan Plateau yak’ and the ‘Hengduan Mountain Alpine yak’, although this conclusion differed from the other classifications. Considering the geographic distribution, ecological factors, history and development of the Chinese yak, it was believed that this classification is reasonable.     

Genetic diversity and relationships of 10 Chinese goat breeds in the Middle and Western China

The genetic variability and relationships among 10 Chinese goat breeds (Shannan white goat, Shanbei white cashmere goat, Funiu goat, Huanghuai goat, Taihang goat, Guanzhong dairy goat, Xinong Saanen goat, Zhongwei goat, Tibetan goat and Inner Mongolia cashmere goat) were studied using 20 microsatellite markers. The mean heterozygosity and the mean polymorphism information content (PIC) for the 10 goat breeds varied from 0.7612 to 0.8390 and 0.7293 to 0.8181, respectively. Huanghuai goat demonstrated the highest genetic variability, and Tibetan goat showed the lowest. G_ST index was 0.052. A unweighted pair group method with arithmetic means (UPGMA) diagram obtained based on Nei standard genetic distance displayed some degree of consistency with their geographical locations and production.     

河南地方山羊品种的遗传多样性

采用18个微卫星位点对河南省5个地方山羊品种（牛腿山羊、槐山羊、河南奶山羊、太行黑山羊和伏牛白山羊）的遗传多样性进行了评价.结果表明：18个微卫星位点在5个山羊品种均为高度多态;5个山羊品种的多态信息含量、群体杂合度、有效等位基因数值较高,说明其遗传多样性和各品种内的遗传变异比较丰富;聚类分析显示,牛腿山羊与太行黑山羊的关系较近,与河南奶山羊的关系较远.群体遗传分化系数和群体遗传距离表明,河南省地方山羊的变异主要存在于品种内,品种间的变异相对较小.结合5个山羊品种的实际生态地理分布,提出了避免近交,并有选择地进行品种间杂交的保种模式.     

5个山羊品种CSN1S2基因的Alw26I酶切

利用PCR-RFLP技术对西农萨能奶山羊、关中奶山羊、陕南白山羊、安哥拉山羊和波尔山羊5个山羊品种的170个个体的αs 2酪蛋白(CSN1S2)基因进行多态性分析,结果表明：扩增大小为310 bp的片段经限制性内切酶Alw26I酶切后表现多态,且5个山羊品种该基因座位均处于Hardy-Weinberg平衡状态。西农萨能奶山羊、关中奶山羊、陕南白山羊、安哥拉山羊和波尔山羊的基因杂合度/有效等位基因数/Shaanon信息熵/PIC值分别为0.1589/1.1889/0.2955/0.1463, 0.4114/1.6981/0.6017/0.5171,0.1653/1.1980/0.3046/0.1516,0.0646/1.0691/0.1463/0.0625,0.0541/1.0572/ 0.1270/ 0.0526。分析结果显示,关中奶山羊的遗传多样性最丰富,表现为高度多态;其次是西农萨能奶山羊和陕南白山羊,而安哥拉山羊和波尔山羊的遗传变异程度最低。     

利用微卫星DNA标记法进行5个肉用绵羊品种的多态性分析和杂种优势率预测

研究选择了与产肉性能相关的5个微卫星标记,分析了这5个位点在杜泊、德国美利奴、特克塞尔、道塞特和右玉本地绵羊5个品种中的遗传多态性.通过遗传分析预测了4个国外引进肉用绵羊品种与右玉本地绵羊的杂种优势,并与实际测定结果进行了比较分析.结果表明,利用微卫星DNA多态性进行品种间杂种优势预测是可行的,杜泊羊与右玉本地绵羊杂交的杂种优势最大,与实际测定结果一致.     

DNA variants of the MHC show location-specific convergence between sheep, goat and cattle

Interspecific convergent evolution in sheep, goat and cattle was analysed with the help of orthologous microsatellite markers. Six of the loci are located in the major histocompatibility complex (MHC) region and three on different chromosomes. Samples from at least 60 animals per autochthonous breed of the three species were collected in central and southeast Anatolia (Turkey) as well as Baden-Württemberg (Germany). Allelic diversity, heterozygosity, population differentiation and genetic distances were calculated. The loci were polymorphic in all species and breeds. Apart from MSDRB, the loci linked to the MHC were similarly polymorphic as compared to the other loci. Allele numbers in the Turkish sheep and in the cattle breeds were higher than in the other breeds. The predominant occurrence of distinct allele lengths per locus differed depending on the species. For the three geographic locations, the genetic distances between species based on the MHC loci were significantly closer in comparison with distances based on quasi-neutral loci. This indicates convergent evolution of the MHC loci between sheep, goat and cattle caused by effects of location and demonstrates an approach for quantifying influences of adaptation on genetic variability.     

Polymorphism in a Microsatellite of the Acrp30 Gene and Its Association with Growth Traits in Goats

Acrp30 plays a critical role in the regulation of glucose and lipid homeostasis. In this study, polymorphism of the Acrp30 gene was detected by PCR-SSCP and DNA sequencing methods in 321 individuals from three goat breeds, and the association of Acrp30 gene polymorphism with growth traits in the three goat breeds was analyzed. A novel insert/deletion (GT)(5) microsatellite sequence was detected in the 5' flanking region of the gene. Three genotypes (AA, AB, and BB) were found in three breeds. There was moderate genetic diversity in the locus in the analyzed populations. Significant associations were observed between the genotypes of the locus and growth traits in the Boer goat population. The chest circumference of individuals with genotype BB was significantly greater than that of individuals with genotype AA.     

Polymorphism of bone morphogenetic protein 4 gene and its relationship with litter size of Jining Grey goats

Two pairs of primers (P1 and P2) were designed to detect single nucleotide polymorphisms of exon 2 and intron 2 of bone morphogenetic protein 4 (BMP4) gene in both high fecundity breed (Jining Grey goat) and low fecundity breeds (Boer, Angora and Inner Mongolia Cashmere goats) by single strand conformation polymorphism. Results showed that no polymorphism was detected for exon 2 (primer P1) of BMP4 gene in four goat breeds. For intron 2 (primer P2), three genotypes (AA, AB and BB) were detected in Jining Grey and Inner Mongolia Cashmere goats, two genotypes (AB and BB) in Angora goats, and only one genotype (AA) in Boer goats. Sequencing revealed one mutation (2203G>A) of BMP4 gene in the genotype BB in comparison to the genotype AA. The differences of litter size between AA, AB and BB genotypes were not significant (P > 0.05) in Jining Grey goats. A pair of primer (P3) was designed to detect polymorphism in the 3' flanking region of BMP4 gene that contained dinucleotide repeated sequence (CA) in the four goat breeds by microsatellite analysis. For primer P3, three genotypes (CC, CD and DD) were detected in four goat breeds. Sequencing revealed one more CA dinucleotide in genotype DD than in genotype CC. The Jining Grey does with genotype CC had 0.55 (P < 0.05) or 0.72 (P < 0.05) kids more than those with genotype CD or DD. These results preliminarily indicated that allele C of BMP4 gene is a potential DNA marker for improving litter size in goats.     

Analysis of 22 heterologous microsatellite markers for genetic variability in Indian goats

The genetic variability of 22 heterologous microsatellite markers was analyzed in two Indian goat breeds, namely Bengal and Chegu. The heterozygosity, polymorphism information content (PIC), and probability of identity of two individuals were calculated for all microsatellite loci in both the breeds. The observed number of alleles varied between 4 and 13 at the studied microsatellite loci. The evaluated microsatellite loci exhibited high mean heterozygosity of 0.69 +/- 0.11 and 0.66 +/- 0.07 in Bengal and Chegu goats, respectively. The mean PIC values of the studied loci in these breeds were 0.79 +/- 0.08 and 0.78 +/- 0.05, respectively. The probability of identity of two random individuals from different breeds, taking into account, all the 22 microsatellite loci was as low as 5.523 x 10(-40). On the basis of these results, we propose that these microsatellite markers may be used with reliability for studying genetic diversity and for identification of individuals in Indian goat breeds.     

Genetic variation within and among three Indian breeds of goat using heterologous microsatellite markers.

The parameters of genetic variation, genetic distances and time of divergence in three Indian goat breeds were studied using 16 cattle microsatellite markers. The mean number of alleles and mean allele size (bp) per microsatellite marker in goats were 5.37 +/- 0.78 and 143.9 +/- 33.75 bp respectively. The average values of heterozygosity and polymorphism information content were 0.54 +/- 0.2 and 0.48 +/- 0.20, respectively. Five of the eight genetic distance methods were highly correlated, revealing a closer relationship between Jamnapari and Barbari goats. A phylogenetic tree constructed from inter-individual distances revealed that the individuals clustered according to the breed to which they belonged, and the Jamnapari and Barbari goats formed a cluster. The divergence times between Sirohi and Jamnapari, and Sirohi and Barbari were approximately 2000 years, while its value between Barbari and Jamnapari goats was approximately 1370 years.     

Polymorphisms in BMP-2 gene and their associations with growth traits in goats

BMPs plays an important role in skeletal development. In this study, PCR-SSCP and DNA sequencing methods were employed to screen the genetic variation of caprine BMP-2 gene in 299 goats from three breeds (Boer goat, Chinese Xuhuai white goat and Chinese Haimen goat). Three fragments of BMP-2 gene were investigated, only 3′ flanking region of BMP-2 gene showed polymorphism. The alignment between nucleotide sequences of AY714781.1 in GenBank and the sequencing results of three PCR products with different patterns revealed that there was one mutation (AY714781.1: g.A172G) in 3′ flanking region of BMP-2 gene, which constructed three genotypes (AA, AB, BB). The frequencies of allele A and genotype AA were dominant in all three breeds. Frequency of allele B in Haimen goat breed was significantly lower than that of the other two breeds. The genotype distributions were in good agreement with Hardy-Weinberg equilibrium (P>0.05) in each breed. The PIC (Polymorphism Information Content) values in three populations were 0.3261, 0.2558, 0.1663 for Boer goat, Xuhuai White goat and Haimen goat respectively. It was indicated that individuals of Boer goats with genotype BB were significantly higher than those of individuals with genotype AA in body trunk index (P<0.01). No polymorphism was detected in the exon3.