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1.
广东汉族人群HLA Ⅰ、Ⅱ基因多态性及单倍型分析 总被引:3,自引:0,他引:3
目的 检测广东汉族人群HLA-A、B、Cw、DRB1基因频率,分析该人群HLAⅠ、Ⅱ等位基因多态性及其单倍型特点。方法 骨髓移植供者160人,抗凝血提取DNA,半量全自动聚合酶链反应-单链构象多态分型检测HLA-A、B、Cw、DRB1基因型。结果 在低分辨水平分别检出HLA-A、B、Cw及DRB1等位基因12、23、11、13个。统计分析呈现显著连锁不平衡的HLA-A-B单倍型9个,B-Cw单倍型20个,A-Cw单倍型7个,HLA-A-DRB1单倍型8个,B-DRB1单倍型9个,Cw-DRB1单倍型10个。结论 广东汉族群体HLA-基因具有较为丰富的多态性,其双座位连锁不平衡单倍型具有地区性遗传特征。 相似文献
2.
Chen S Hong W Shao H Fu Y Liu X Chen D Xu A 《International journal of immunogenetics》2006,33(6):439-445
Tibetans live in Qinghai-Tibet Plateau rising about 4000 m a.s.l. in south-west China. Archaeological evidences suggested that there have been humans living in Tibet at least 5000 years ago. However, Tibetan earlier history remains elusive. In the present study, allelic distribution of human leucocyte antigen (HLA)-A, -B and -Cw in 158 unrelated Tibetan Chinese was investigated using sequencing-based typing methods, and a total of 25 HLA-A, 45 HLA-B and 20 HLA-Cw alleles were identified. A*24G1 (27.2%), B*51G1 (16.8%), Cw*04G1 (13.3%) and Cw*070201G1 (13.3%) are the most common HLA-A, -B and -Cw alleles. The most frequently detected haplotypes were A*24G1-B*51G1-Cw*140201 (3.6%), A*24G1-B*51G1 (6.8%), A*02G1-Cw*070201G1 (6.5%) and B*51G1-Cw*140201 (5.0%). Chi-squared test suggested that all three loci fitted the Hardy-Weinberg expectations. No evidence for a departure from selective neutrality at the HLA-A and -B loci was observed. However, significant departure of the observed homozygosity from the expected values was found for HLA-Cw. Though the contemporary Tibetans inhabit the south-west China, Nei's genetic distance measure based on frequencies of HLA-A, -B and -Cw indicated that Tibetans were closer to northern Han Chinese, Mongolian Chinese, Koreans and Japanese rather than to southern Han Chinese. The corresponding dendrogram constructed according to the neighbour-joining method supported that Tibetans separated from southern Han and located in North-East Asian cluster which included northern Han Chinese and Mongolian Chinese. These data were in good agreement with language classification and with a recent hypothesis that Tibetan might originate from northern China along Yellow river. 相似文献
3.
Genes in the HLA complex, the human major histocompatibility complex (MHC), encode polymorphic HLA class I and II molecules that help T lymphocytes recognise and respond to foreign antigens. Certain HLA class I allotypes also regulate the response of natural killer cells. HLA class I and II molecules with little or no polymorphism contribute a variety of functions to the immune response, as do class I molecules coded by genes outside of the HLA region. Knowledge of the organisation of HLA class I and II genes, of the nucleotide sequences of their alleles, and the three-dimensional structures of their protein products, has facilitated analysis of the evolution and polymorphism of HLA class I and II genes and molecules. In turn, these analyses have provided insight into the mechanisms and selective forces driving change in the HLA complex. 相似文献
4.
Association of HLA genes with ankylosing spondylitis in Han population of eastern China 总被引:1,自引:0,他引:1
Fang M Chen R Cai Q Duan S Lv K Cheng N Sun S 《Scandinavian journal of immunology》2007,65(6):559-566
Ankylosing spondylitis (AS) is a chronic inflammatory disorder with a multifactorial genetic basis. HLA-B27 was reported with the greatest susceptibility to AS but did not act alone. The aim of this study was to search for other gene(s) associated with AS independently of HLA-B27 using 13 microsatellite markers spanning 1.5 Mb from locus TAP1 to HLA-Cw and a single-nucleotide polymorphism marker within NFkappaBIL1 gene promoter. Genotyping for microsatellites was performed in 175 AS patients of eastern Chinese and 219 ethnically matched healthy controls using polymerase chain reaction with fluorescence-labelled primers, whereas the SNP marker was genotyped by direct DNA sequencing. Allele as well as haplotype frequencies were compared between cases and controls, and a linkage disequilibrium analysis was performed to estimate the LD relationship between the candidate regions. The frequencies of alleles D6S2811*128, STR_MICA*A5.1 and D6S2672*109, as well as haplotypes D6S2811*128-D6S2927*213-D6S2810*340, D6S2927* 221-D6S2810*350-MICA*A5.1, and D6S2810*350-MICA*A5.1-D6S2800* 136 were significantly increased in B27-positive AS patients when compared with B27-positive controls. The results indicated that there may be other gene(s) within the HLA region, especially around locus HLA-B or HLA-Cw, with susceptibility to AS independently of HLA-B27. 相似文献
5.
In the present study, the polymorphism of human leucocyte antigen class II genes was investigated by the sequence-based typing method in two Chinese populations: the Miaos (n = 85) from Guizhou province and the Yaos (n = 66) from Yunnan province. These two populations exhibited certain similarity in their allelic distributions. Among 24 DRB1 alleles detected, DRB1*150101, DRB1*140101, DRB1*160201 and DRB1*090102 in Miao and DRB1*120201, DRB1*140101, DRB1*150101 and DRB1*090102 in Yao were highly predominant. Sixteen DQB1 alleles in total were found in these two populations among which DQB1*050201, DQB1*060101/060103 and DQB1*030101/0309 in both Miao and Yao and DQB1*050301 in Yao were commonly observed. In the 13 DPB1 alleles detected, the most frequent allele was DPB1*0501 in Miao and Yao followed by DPB1*02 and DPB1*1301. Frequent comparisons with other Chinese populations suggested the southern Chinese feature for both the Miao and Yao nationalities. 相似文献
6.
Polymorphism of TAPASIN and its linkage disequilibria with HLA class II genes in the Japanese population 总被引:1,自引:0,他引:1
H. Furukawa K. Kashiwase T. Yabe Y. Ishikawa T. Akaza K. Tadokoro S. Tohma T. Inoue K. Tokunaga K. Yamamoto T. Juji 《Tissue antigens》1998,52(3):279-281
Abstract: Tapasin plays an important role in HLA class I assembly. The gene has been mapped on the human MHC region. We identified two alleles of TAPASIN in the Japanese population and analyzed the association of the alleles with HLA-DPB1, -DQB1 and -DRB1 alleles. The allele frequencies of TAPASIN*01 and *02 were estimated to be 0.37 and 0.63, respectively, in the Japanese population. TAPASIN showed strong linkage disequilibrium with the HLA-DPB1 locus. Several frequent four-locus haplotypes were identified, including DRB1*0901-DQB1*0303-DPB1*0501-TAPASIN*02, DRB1*0901-DQB1*0303-DPB1*0201-TAPASIN*02 and DRB1*1302-DQB1*0604-DPB1*0401-TAPASIN*02. 相似文献
7.
HLA多态性在广东汉族人群分布的特殊性 总被引:30,自引:1,他引:29
目的探讨人类白细胞抗原(humanleucocyteantigenHLA)在广东汉族群体中的遗传特征。方法采用免疫磁珠单抗血清学技术进行HLA-A、B分型和聚合酶联反应-序列特异性引物(sequencespecificprimersPCR-SSP)进行HLA-DR、DQ分型,调查了406名广东汉族健康献血员。结果识别HLA-A、B、DR和DQ座位106个特异性,4142条单倍型,发现HLA-A33-B58-DR17-DQ2和HLA-A2-B46-DR9-DQ9在广东汉族中呈现高频率。结论HLA-A33-B58-DR17-DQ2和HLA-A2-B46-DR9-DQ9,这两条单倍型在广东汉族人群中的分布频率与相关文献其他民族和人群相比为显著连锁不平衡单倍型。 相似文献
8.
目的 探索杀伤细胞免疫球蛋白样抑制性受体 (iKIR)及其人白细胞抗原 (HLA)配体在中国广东汉族人群中的分布。方法 对 79例广东汉族人 ,采用引物序列特异性扩增法检测其iKIR表型 ,HLA A、B、Cw表型。HLA A、B分型采用BiotestHLA分型 (SSP)试剂盒 ,HLA C分型采用半量全自动PCR SSO分型。结果 KIR2DL1、2DL2、2DL3、2DL4、2DL5、3DL1、3DL2、3DL3的表型频率分别为0 .87、0 .13、0 .5 2、1、0 .18、0 .94、1和 0 .99。个体 86 .1%表达 1种以上iKIR HLA配对 ,其中 3DL1 HLA Bw4配对表型频率为 6 9.6 % ,2DL2 C2为 4 3.0 % ,2DL1 C1为 16 .5 %。由于不表达HLA A3,该组人群中无 3DL2 HLA A3受体配体对。 13.9%人群缺乏iKIR HLA配对。结论 约 7/ 8的广东汉族个体表达1种以上iKIR HLA配对 ,以 3DL1 HLA Bw4配对为主 ;约 1/ 8个体缺乏已知的iKIR HLA配对。 相似文献
9.
The allelic distribution of human leukocyte antigen (HLA) class I genes (HLA-A, HLA-B, and HLA-Cw) of the population from the State of Pernambuco in Northeastern Brazil was studied in a sample of 101 healthy unrelated individuals. Low to medium resolution HLA class I typing was performed using polymerase chain reaction-amplified DNA hybridized to sequence specific primers (PCR-SSPs). Twenty allele groups were detected for HLA-A, 28 for HLA-B, and 14 for HLA-Cw. The most frequent alleles were HLA-A*02(0.2871), HLA-B*15(0.1238), and HLA-Cw*04(0.2277), and the most frequent genotypes were A*02/A*02(0.0990), B*15/B*15(0.0594), and Cw*04/Cw*04 and Cw*07/Cw*07, both with a frequency of 0.0792. The observed heterozygosity for the studied loci was 79.21% for HLA-A, 87.13% for HLA-B, and 77.23% for HLA-Cw. The most frequent haplotype was A*02-Cw*04-B*35(0.0485), which is also present in Western European, Amerindian, and Brazilian Mulatto populations, but absent in African populations. Taken together, these data corroborate the historic anthropological evidences of the origin of the Northeastern Brazilian population from Pernambuco. 相似文献
10.
Ferrer A Nazábal M Companioni O Fernández de Cossío ME Camacho H Cintado A Benítez J Casalvilla R Sautié M Villareal A Díaz T Marrero A Fernández de Cossío J Hodelin A Leal L Ballester L Novoa LI Middleton D Dueñas M 《Human immunology》2007,68(11):918-927
The extreme polymorphism found at some of the human leukocyte antigen (HLA) system loci makes it an invaluable tool for population genetic analyses. In the present study the genetic polymorphism of the Cuban population was estimated at HLA-A, -B, and -Cw loci by DNA typing. HLA class I allele and haplotype diversity were determined in 390 unrelated Cuban individuals (188 whites and 202 mulattos) from all over the country. In whites 19, 27, and 14 allele families for the HLA-A, -B, and -Cw loci, respectively, were identified. In mulattos, for the same loci, 20, 18, and 14 allele families were identified. Allele and haplotypes frequencies, comparisons with other worldwide populations based on genetic distances, neighbor-joining dendrograms, and correspondence analyses were estimated. Most of the identified allele groups and haplotypes are also common to sub-Saharan African and Europeans populations. However, Amerindian and Asian alleles were also detected at lower frequencies. The results clearly reveal the high diversity and interethnic admixture of the studied population. Our results provide useful information for the further studies of the Cuban population evolution and disease association in terms of HLA class I genes. 相似文献
11.
目的:定量检测正常人血清中可溶性人白细胞抗原-I(sHLA-I),以探讨山西汉族人群的正常参考值。方法:ELISA法检测血清sHLA-I类抗原水平。将不同浓度的标准品和待捡血清分别加入包被有特异性sHLA-I抗体的酶标板,与生物素化的sHLA-I、辣根过氧化物酶(HRP)标记的链霉亲和素共同孵育,弃上清并用洗涤液洗涤,加底物应用液四甲基联苯胺(TMB)显色,以酶标仪450nm测定吸光度值,根据不同浓度标准品显色后测得的吸光度值绘制标准曲线,测定60例健康山西人的sHLA-I含量。结果:ELISA法能够准确检测sHLA-I含量,60例健康山西人的sHLA-I含量为(382.62±106.68)ng·ml-1。结论:山西汉族人群sHLA-I正常值为(382.62±106.68)mg·ml-1。 相似文献
12.
Pâmela Portela Joice Merzoni Juliana D. Lindenau Daniel C. Damin Timothy John Wilson Rafael Roesler Gilberto Schwartsmann Luiz Fernando Jobim Mariana Jobim 《Human immunology》2017,78(3):263-268
Colorectal cancer (CRC) can occur anywhere in the colon or rectum and represents the third most common cancer in the world in both sexes. Natural killer cells (NK) are part of the innate immune system recognizing class I HLA molecules on target cells through their membrane receptors, called killer cell immunoglobulin-like receptors (KIR). The aim of our study was to evaluate the association between the KIR genes and HLA ligands in patients with colorectal cancer and healthy controls. We examined the polymorphism of 16 KIR genes and their HLA ligands in 154 caucasoid CRC patients and 216 controls. When both groups were compared, no significant differences were found for HLA ligands and KIR genes after Bonferroni correction. However, the Bx haplotypes (heterozygous and homozygous for the haplotype B) were more frequent in controls, when compared with patients. These findings suggest that individuals with Bx haplotypes could have some protection to colorectal cancer. The hypothesis is not related with the presence of a special KIR gene and HLA ligand related to the disease, but to the presence of several activating genes in the individuals with no better action of one in relation to other. Further studies to confirm this observation are warranted. 相似文献
13.
Polymorphism of human leukocyte antigen-DRB1, -DQB1, and -DPB1 genes of Shandong Han population in China 总被引:6,自引:0,他引:6
In the present study, polymerase chain reaction-sequence-based typing (PCR-SBT) was used to analyze human leukocyte antigen (HLA)-DRB1, -DQB1, and -DPB1 alleles of 98 unrelated healthy Shandong Han individuals. A total of 60 alleles, in which 28 in DRB1, 15 in DQB1 and 17 in DPB1 were found. Among the 28 detected DRB1 alleles, DRB1*150101, DRB1*070101, DRB1*090102, DRB1*120201, and DRB1*080302 were commonly observed, with frequencies of 16.3%, 11.2%, 10.2%, 8.2%, and 5.6%, respectively. The most predominant DQB1 allele was DQB1*030101/0309 with the frequency of 20.4%, followed by DQB1*0201/0202 (14.8%), DQB1*0602 (14.3%), DQB1*030302 (12.2%), and DQB1*060101/060103 (10.7%). Of the 17 detected DPB1 alleles, DPB1*0501 was the most frequent allele with the frequency of 37.2%. DPB1*020102 (18.4%), DPB1*040101 (11.2%), DPB1*0402 (7.1%), and DPB1*1701 (6.6%) were also very frequent alleles. A total of 53 estimated DRB1-DQB1 two-locus haplotypes were observed in Shandong Han population, of which DRB1*150101-DQB1*0602 was the most predominant, followed by DRB1*090102-DQB1*030302, DRB1*070101-DQB1*0201/0202 DRB1*120201-DQB1*030101/0309, and DRB1*080302- DQB1*060101/060103. The distribution of the HLA class II alleles and haplotypes frequencies as well as the dendrogram showed that the Shandong Han population belongs to the northern group of Chinese. The data have implications for anthropological studies and disease associations. 相似文献
14.
Locus and population specific evolution in HLA class II genes 总被引:1,自引:0,他引:1
A. M. VALDES S. K. McWEENEY D. MEYER M. P. NELSON G. THOMSON 《Annals of human genetics》1999,63(1):27-43
The population genetics of the HLA class II loci was studied with reference to variation in the frequency of (a) alleles at a locus and (b) amino acids at specific sites. Variation was surveyed at 4 loci (DRB1, DQA1, DQB1, and DPB1) in 22 populations from the Twelfth International Histocompatibility Workshop (Saint-Malo, 1996). Allele and amino acid variation was measured by computing heterozygosity and the effective number of alleles. Substantial variations in polymorphism were observed among the various populations and loci studied. In the majority of the populations, DRB1 has the highest heterozygosity and effective number of alleles. As previously shown, the Amerindian populations have lower levels of allelic diversity when compared to other populations. At the amino acid level, DRB1 antigen recognition sites (ARS) have the highest heterozygosities and effective number of alleles. For the other loci (DPB1, DQA1, and DQB1) for which there is no crystal structure and for which ARS sites were inferred from DRB1, non-ARS sites were often among the sites with highest levels of variation. It is possible that these putative non-ARS sites do play a role in antigen presentation.
The homozygosity test for neutrality was applied to allele and amino acid data. Of the four HLA class II loci studied, only DPB1 failed to show evidence of balancing selection. DQB1 and DQA1 depart significantly from neutrality in the largest number of populations. Genetic distances between populations were computed based on frequency of alleles and amino acids at ARS sites. 相似文献
The homozygosity test for neutrality was applied to allele and amino acid data. Of the four HLA class II loci studied, only DPB1 failed to show evidence of balancing selection. DQB1 and DQA1 depart significantly from neutrality in the largest number of populations. Genetic distances between populations were computed based on frequency of alleles and amino acids at ARS sites. 相似文献
15.
M.‐C. Grimaldi B. Crouau‐Roy L. Contu J.‐P. Amoros 《International journal of immunogenetics》2002,29(2):101-107
Three human leucocyte antigen (HLA) class I loci (HLA‐A, ‐B and ‐Cw) were typed for the first time at the DNA level in the Corsican population. This analysis was performed on 100 individuals of Corsican origin living in central Corsica (46 individuals) and in south‐western Corsica (54 individuals). The genetic structure of these two subpopulations was analysed on the basis of the molecular polymorphisms of the HLA‐A, ‐B and ‐Cw genes. A phylogenetic and a haplotypic analysis were performed. The genotypic analysis did not detect genetic differentiation. Examination of the allelic and haplotypic frequencies did, however, reveal some significant differences between the two zones. Similarities with the Sardinian population were found, and were particularly evident in the south‐western sample. However, Corsica has probably been subject to greater West European influence, which can be seen in the Corte sample (Haute Corse). 相似文献
16.
17.
目的 探讨我国部分省份(地区)汉族人群HLA-Ⅰ类经典基冈座位HLA-A、HLA-B、HLA-Cw位点的群体遗传学特点及其基因频率分布的地区差异.方法 选取1014例无关汉族拟行造血干细胞移植治疗患者及其健康家系供者的血液样本,提取基因组.DNA后,采用序列特异性引物聚合酶链式反应(PCR-SSP)分型技术进行HLA-A、HLA-B、HLA-Cw位点基因分型,分析不同地区汉族人群及不同种族间的基因频率分布特征.基于文献报道的我国不同地区汉族人群及不同种族的HLA-Ⅰ类基因频率资料,计算种群间遗传距离(D),比较不同地区汉族人群及不同种族间遗传距离差异.结果 Hard-Weinberg吻合度检验表明,本研究抽样群体适于进行遗传学统计分析.HLA-A位点共检测出14种基因型,最常见的是A*02(0.330)、A*11(0.240)、A*24(0.155)、A*33(0.075);HLA-B位点共检测出27种基因型,最常见的是B*13(0.134)、B*15(0.143)、B*40(0.133)、B*46(0.102);HLA-Cw位点共检测出13种基因型,最常见的是Cw*01(0.157)、Cw*03(0.247)、Cw*07(0.181)、Cw*08(0.106).群体汉族与其他人种间HLA-A、HLA-B基因频率差异均有统计学意义(P<0.05);除兰州汉族人群仅同南方汉族、湖南、山东、江苏、台湾汉族人群间HLA-A、HLA-B基因频率差异有统计学意义(P<0.05)外,其余各地区汉族人群间HLA-A、HLA-B基因频率差异均有统计学意义(P<0.05).各地区汉族人群间平均遗传距离D=0.164,辽宁和北方汉族人群间遗传距离(D=0.064)最小,江苏与湖南汉族人群间遗传距离(D=0.299)最大;不同地区汉族人群间遗传距离普遍小于种族间遗传距离.结论 我国不同地区汉族人群HLA-Ⅰ类基因频率分布存在显著差异,但其差异要明显小于世界不同人种间的分布差异.我国汉族人群所特有的HLA-Ⅰ类基因频率分布格局资料对区域性疾病的个性化治疗、遗传易感性及疾病防治等研究具有很好的理论及应用价值. 相似文献
18.
目的探讨我国部分省份(地区)汉族人群HLA-I类经典基因座位HLA-A、HLA-B、HLA-Cw位点的群体遗传学特点及其基因频率分布的地区差异。方法选取1014例无关汉族拟行造血干细胞移植治疗患者及其健康家系供者的血液样本,提取基因组DNA后,采用序列特异性引物聚合酶链式反应(PCR-SSP)分型技术进行HLA-A、HLA-B、HLA-Cw位点基因分型,分析不同地区汉族人群及不同种族间的基因频率分布特征。基于文献报道的我国不同地区汉族人群及不同种族的HLA-I类基因频率资料,计算种群间遗传距离(D),比较不同地区汉族人群及不同种族间遗传距离差异。结果Hard-Weinberg吻合度检验表明,本研究抽样群体适于进行遗传学统计分析。HLA-A位点共检测出14种基因型,最常见的是A^*02(0.330)、A^*11(0.240)、A^*24(0.155)、A^*33(0.075);HLA-B位点共检测出27种基因型,最常见的是B^*13(0.134)、B^*15(0.143)、B^*40(0.133)、B^*46(0.102);HLA-Cw位点共检测出13种基因型,最常见的是Cw^*01(0.157)、Cw^*03(0.247)、Cw^*07(0.181)、Cw^*08(0.106)。群体汉族与其他人种间HLA-A、HLA-B基因频率差异均有统计学意义(P〈0.05);除兰州汉族人群仅同南方汉族、湖南、山东、江苏、台湾汉族人群间HLA-A、HLA-B基因频率差异有统计学意义(P〈0.05)外,其余各地区汉族人群间HLA-A、HLA-B基因频率差异均有统计学意义(P〈0.05)。各地区汉族人群间平均遗传距离D=0.164,辽宁和北方汉族人群间遗传距离(D=0.064)最小,江苏与湖南汉族人群间遗传距离(D=0.299)最大;不同地区汉族人群间遗传距离普遍小于种族间遗传距离。结论我国不同地区汉族人群HLA-I类基因频率分布存在显著差异,但其差异要明显小于世界不同人种间的分布差异。我国汉族人群所特有的HLA-I类基因频率分布格局资料对区域性疾? 相似文献
19.
上海人群中TAP、LMP和HLA-DM基因多态性研究 总被引:5,自引:0,他引:5
调查上海人群中抗原处理相关基因TAP、LMP和HLA-DM的分布情况,并探索这些基因与自身免疫病类风湿关节炎(RA)、IgA肾炎(IgAN)和多发性硬化症(MS)的可能关联。应用PCR-SSO或PCR-RFLP技术对80名无血缘关系的上海地区正常人及156名RA患者、60名IgAN患者和21名MS患者作了TAP1、TAP2、LMP2、HLA-DMA和HLA-DMB基因分型。并作了两位点连锁不平衡分析。在该群体中,(1)共观察到4个TAP1、6个TAP2、2个LMP2、4个HLA-DMA和4个HLA-DMB等位基因;(2)在TAP1B-TAP2A、TAP1B-LMP2H和TAP2D-DMA*0101存在连锁不平衡(Pc<0.05);(3)本人群中IgAN和MS的遗传易感性与抗原处理相关基因无关,而RA患者中DMB*0101基因频率降低(P<0.01),TAP1C和DMB*0104等位基因频率显著升高(P<0.01)。比较分析表明,上海人群中抗原处理相关基因多态性与国外其他人种中的报道相似,本人群中IgAN和MS与抗原处理相关基因不关联,而TAP1C和DMB*0104等位基因可能是RA的遗传易感基因。 相似文献
20.
Polymorphism analysis of four canine MHC class I genes 总被引:1,自引:0,他引:1
Abstract: We have studied the variability of four structurally complete dog leukocyte antigen (DLA) class I genes, termed DLA-12, -88, -79 and -64, in a population of mixed breed, unrelated dogs. The human HLA and canine DLA loci share a high degree of similarity in terms of gene structure. This analysis focused on the first three exons of each of four complete canine genes. Exons two and three are the major source of polymorphism in the corresponding human genes. In this analysis, DLA-88 was found to be significantly more polymorphic than the other three genes, with 44 distinct alleles observed among 63 mixed breed, unrelated dogs. The remaining genes had between one and four alleles when examined in 25 dogs. This work was carried out as part of an effort to develop an MHC typing system for the dog, which is critical to the further development of preclinical studies of hematopoietic stem cell and solid organ transplantation in the canine model. 相似文献