河南汉族人群血小板抗原HPA1-16bw基因多态性研究

摘要：目的：研究河南地区汉族人群血小板抗原基因分布频率,建立地区性血小板抗原基因库,为血小板配合输注提供实验依据。 方法：用序列特异性引物聚合酶链反应（PCR-SSP）对160例无血缘关系的河南汉族体检健康者进行HPA1-16bw系统基因分型。 结果：HPA1-6和HPA-15基因频率分别为1a 0.987 5,1b 0.012 5; 2a 0.946 9,2b 0.053 1; 3a 0.590 6,3b 0.409 4; 4a 0.996 9,4b 0.003 1; 5a 0.990 6,5b 0.009 4; 6a 0.981 2,6b 0.018 8;15a 0.540 6,15b 0.459 4。 HPA7-14bw,16bw仅检测到a/a等位基因,基因频率均为1.000 0。经χ²检验各系统HPA符合Hardy-Weinberg平衡法则。HPA基因分布存在种族和地区差异。 结论:河南汉族人HPA-15 和HPA-3基因型杂合率最高。HPA基因分型有助于输注血小板时降低免疫性血小板减少症的发生概率。     

深圳地区汉族人类血小板抗原1-6系统基因多态性分析

目的 研究人类血小板抗原基因多态性,为人类学研究及临床输血实践提供依据。方法 采用PCR-SSP方法对深圳地区222名汉族随机献血者HPA1-6系统进行基因分型研究,对其基因及基因型频率进行统计,并与HPA在不同人群中的分布进行对比分析。结果 在6个HPA系统中,HPA-3基因型的杂合程度最高,HPA-3a/3a、HPA-3a/3b、HPA-3b/3b的频率分别为0.265 8,0.518 0,0.216 2;其余5个HPA系统均以a/a纯合子为主,a基因的频率范围为0.997 7～0.955 0,且均未发现b/b纯合子。1b、4b的基因频率很低,分别为0.009 O和0.002 3。结论 深圳汉族人群HPA1-6系统的基因频率与中国台湾人及中国香港人均很相似(P>0.05)。HPA-1、HPA-5与美国黑人、白人及荷兰人差异显著(P<0.05);HPA-2、HPA-3与日本人、韩国人、美国黑人、白人差异显著(P<0.05);HPA-4与日本人差异显著(P<0.05)。在未来的临床实践中要警惕HPA-2,3,5,6系统同种抗体导致的同种免疫血小板减少综合征的可能。     

浙江汉族人群血小板抗原1-16多态性调查

目的了解浙江汉族人群血小板抗原1-16多态性分布。方法采用PCR-SSP方法对120份浙江无血缘关系汉族样本作HPA-1—16等位基因分型。结果HPA-1b、-2b、-3b、-6bw、-15b的基因频率分别为0.0125、0.0542、0.3833、0.0125、0.4833,未检出HPA-4b、-5b、-7bw、-8bw、-9bw、-10bw、-11bw、-12bw、-13bw、-14bw、-16bw等位基因。浙江汉族人群HPA-3、15抗原系统血小板随机输注错配概率分别为0.36、0.37。结论浙江汉族人群HPA多态性分布与中国其他地区汉族人群比较没有差异,HPA-3和15系统多态性较丰富,因此在随机血小板输注或胎母之间比较容易发生同种免疫反应。     

云南汉族血小板献血者HLA-A、B和HPA基因多态性的分析

目的研究云南地区汉族血小板献血者HLA-A、B基因和HPA1-17基因多态性,建立已知型血小板献血者基因数据库。方法分别采用PCR-SSOP和PCR-SSP方法对1 000名云南地区无血缘关系的汉族血小板献血者做HLA-A、B和HPA1-17系统基因分型,计算基因型频率、基因频率,并与其他人群进行比较。结果在云南地区人群中共检出HLA-A位点14个,HLA-B位点35个。A*02(35.81%)、A*11(35.42%)和A*24(17.72%)3个等位基因为云南汉族人群HLA-A座位的主要等位基因;B*46(12.87%)、B*40(60)(10.83%)和B*15(62)(9.78%)3个等位基因为云南汉族人群HLA-B座位的主要等位基因。每个样本均检测到HPA-1a、2a、4a-14a、16a、17a基因;HPA-4a、7a-14a、16a、17a呈现单态性,未检测出相应的等位基因HPA-b;对于HPA-1、2、5、6主要以a/a纯合子居多,a/a基因型频率分别是0.989、0.960、0.990、0.980,没有b/b纯合子出现。在HPA1-17中,具有最高杂合度的是HPA-15,基因型HPA15a/15a、HPA15a/15b、HPA15b/15b频率分别是0.392、0.360、0.248;HPA-3在其次,基因型HPA3a/3a、HPA3a/3b、HPA3b/3b频率分别是0.339、0.467、0.194。经χ2检验,结果符合Hardy-Weinberg遗传平衡定律。结论云南地区汉族血小板献血者HLA-A、B和HPA1-17基因频率与南方汉族接近,也呈现其自身特点。应建立本地区的血小板供者分型数据库。     

石家庄汉族血小板捐献者HPA1-17基因多态性分析

目的建立石家庄地区已知HPA基因型别单采血小板捐献者基因资料数据库,分析石家庄地区3591名汉族血小板捐献者HPA基因多态性分布特点。方法 HPA基因分型采用聚合酶链反应—序列特异引物(PCR-SSP)方法,计算等位基因频率、基因型频率及HPA-1～17组合型频率。结果 3 591名无血缘关系的血小板捐献者HPA基因HPA-7～14、HPA-16、HPA-17系统均为aa纯合子,未检出b等位基因。HPA-1～6、15中杂合度最高的为HPA-3系统,不配合率为37.44%;其次为HPA-15系统,不配合率为37.40%;HPA-4系统的杂合度最低,不配合率仅为0.38%;与国内部分地区人群数据比较分析,发现石家庄地区汉族血小板捐献者HPA-5系统分布与国内其他地区人群存在显著差异。结论建立了石家庄地区血小板捐献者HPA-1～17基因分型数据库,可为患者提供HPA相合的血小板,对减少临床血小板输注无效的发生具有重要意义。     

张家口地区机采血小板捐献者HPA分型研究

目的:分析河北省张家口地区血小板捐献者血小板特异性抗原HPA1-5,15系统的基因多态性。方法:采集血小板捐献者静脉血并提取DNA,采用聚合酶链-序列特异性引物(PCR-SSP)法进行血小板特异性抗原分型,计算基因频率、基因型频率并与国内外其他地区进行比较是否存在差异及是否表现地区特异性。结果:HPA-1、HPA-2、HPA-4系统中基因表达均为纯合子aa,未出现表达纯合子bb的存在者,其中HPA-1和HPA-4系统各发现杂合子ab表达1例(1%),HPA-2系统发现杂合子ab表达14例(14%);HPA-5系统基因表达主要为纯合子aa(98%),极少数表达纯合子bb(2%);HPA-3和HPA-15系统基因表达杂合程度较高,HPA-3系统基因表达aa、ab、bb表达比例分别为46%、40%、14%,HPA-15系统基因表达aa、ab、bb表达比例分别为21%、64%、15%。结论:张家口地区血小板特异性抗原HPA1-5,15系统基因频率具有本地区特点;HPA-3和HPA-15系统基因表达杂合程度较高,引发同种免疫及血小板输注无效的可能性较大,因此应引起注意。     

中国南京地区汉族人群血小板HPA-1-18遗传多态性研究

本研究旨在调查南京地区无关健康人群人类血小板抗原1-18(HPA-1-18)等位基因频率,为输血患者寻找相容性血小板提供可靠依据。使用PCR-SSP方法对300例南京地区非血缘健康志愿者血液样品进行人血小板抗原1-18(HPA-1-18)等位基因分型。结果表明,南京地区300例非血缘人群HPA等位基因频率分别为:HPA-2a 0.9183和-2b 0.0817;HPA-3a 0.6100和-3b 0.3900;HPA-5a 0.9733和-5b 0.0267;HPA-6a 0.9883和-6b 0.0117;HPA-15a 0.5250和-15b 0.4750。HPA-1a,-4a,-7a-14a和HPA-16a-18a均是纯合子。结论:HPA抗原等位基因频率存在种族和地域差异。南京地区HPA抗原等位基因频率显示具有自身特点。HPA-3和HPA-15是最常见的杂合子,因此必须关注HPA在血小板临床输血中的作用。     

HPA-1-28w基因分型检测技术体系的建立和广西瑶族、汉族人群HPA-1-28w基因多态性研究

目的建立HPA-1-28w基因分型检测技术体系并用以研究广西瑶族和汉族人群的血小板抗原(HPA)-1-28w基因多态性。方法通过设计序列特异性引物和优化PCR反应条件,摸索HPA-1-28w基因分型检测技术体系,其组成包括前期已建立的HPA-1-17w多重PCR-SSP技术和新研发的HPA-18-28w PCR-SSP方法 2部分组成。使用10例已预先测序确定HPA-18-28w基因型和20例已预先使用商品试剂盒检测HPA-18-21w基因型的本研究广西瑶族标本,对新研发的HPA-18-28w PCR-SSP方法做验证。应用所建立的HPA-1-28w基因检测技术对广西地区无血缘关系的1424名健康瑶族人和908名健康汉族人做HPA-1-28w基因分型和多态性分析。结果所建立的HPA-1-28w基因分型技术系统,不仅对HPA-18-28w基因的分型结果与对验证用标本的测序分型结果完全一致,而且对HPA-18-21w基因的分型检测结果与商品试剂盒的分型结果完全一致。广西瑶族人群的HPA各等位基因频率分别为:HPA-1a 0.998 2、1b 0.001 8,2a 0.874 6、2b 0.125 4,3a 0.661 5、3b 0.338 5,5a 0.996 8、5b 0.003 2,6a 0.9786、6bw 0.021 4,15a 0.407 7、15b 0.592 3;汉族人群HPA各等位基因频率分别为:HPA-1a 0.998 3、1b 0.001 7,2a0.957 6、2b 0.042 4,3a 0.532 5、3b 0.467 5,4a 0.999 4、4b 0.000 6,5a 0.984 0、5b 0.016 0,6a 0.989 0、6bw 0.011 0,15a 0.534 1、15b 0.465 9;广西瑶族和汉族人群的HPA-7-14w、HPA-16-28w基因均以aa纯合子形式存在。在本组广西瑶族人群中发现2例罕见的HPA-6bb纯合子基因型个体,而在汉族人群中发现了1例中国人群中罕见的HPA-4ab基因型个体。结论建立了完善的HPA-1-28w PCR-SSP基因分型检测技术体系,并成功应用于广西瑶族和汉族人群的HPA-1-28w基因筛查和分型研究;广西瑶族、汉族人群HPA基因频率分布在HPA-2,-3,-5,-15系统和HPA-6w等均不同(P0.05),藉此有助于了解广西瑶族和汉族人群HPA的免疫学特点。     

黑龙江省汉族人群血小板抗原1～17系统基因多态性研究

目的探讨黑龙江省汉族人群人类血小板同种抗原(Human platelet alloantigen,HPA)1~17系统基因多态性及其表达频率,确定有临床意义的血小板抗原系统。方法选择123例汉族的健康无血缘关系的人群为研究对象,采用聚合酶链-序列特异性引物(PCR-SSP)技术,对HPA1-17系统等位基因进行分型,分别计算其基因频率、基因型频率,并与国内外不同人群进行比较。结果黑龙江省汉族人群HPA-1a、2a、3a、5a、6a、15a基因频率分别是0.987 8、0.9594、0.682 8、0.971 5、0.983 7、0.479 6,HPA-4a、7a~14 a、16 a和17a均为1.0;HPA-1b、2b、3b、5b、6b、15b基因频率分别是0.012 2、0.040 7、0.317 1、0.028 5、0.016 3、0.520 4,未检测出HPA-4b、7b~14b、16b和17b。统计汉族人群HPA基因组合型及其频率,发现共有24种HPA基因组合型,前3种基因组合型频率均10%(占55.28%),其余21种基因组合型的频率均7.5%(44.72%)。结论黑龙江省汉族健康人群HPA1~17基因频率的分布与其他地区和国家相比具有本地区人群特点。HPA-3、15系统具有高度多态性,在随机血小板输注中,供受者HPA-3、15系统不配合率分别为33.93%、37.46%,易发生同种免疫反应。     

献血者血小板1-16抗原基因遗传多态性分析及已知HPA型供者数据库的建立

本研究的目的是分析人类血小板抗原（human platelet antigen,HPA）基因多态性,根据分布频率来判断HPA抗原不配合比率以及抗体产生的机会,确定有临床意义的血小板抗原系统,并建立邯郸地区血小板基因频率数据库和供者库.采用SSP-PCR方法对邯郸地区148名随机献血者进行HPA1-16抗原32个等位基因的检测分析,并与不同人群的分布频率进行比较.结果表明：每个样本均检测到HPA-1a、2a、4a-14a、16a基因;HPA-4a、7a-14a、16a呈现单态性,未检测出相应的等位基因HPA-b;对于HPA-1、-2、-5、-6主要以a/a纯合子为多,a/a基因型频率分别是0.9595、0.8108、0.9865、0.9797,没有b/b纯合子出现.在HPA1-16中,具有最高杂合度的是HPA-15,基因型HPA15a/15a、HPA15a/15b、HPA15b/15b频率分别是0.2230、0.5270、0.2500;HPA-3在其次,基因型HPA3a/3a、HPA3a/3b、HPA3b/3b频率分别是0.3851、0.5135、0.1014.经x2检验,结果符合Hardy-Weinberg遗传平衡定律.邯郸地区随机献血者HPA1-5系统基因频率与石家庄地区相似（P＞0.05）;与我国台湾人群进行HPA1-13、HPA-15的比较,HPA-1、-2、-6具有明显的不同（P＜0.05）,其它相似（P＞0.05）;与韩国人群进行HPA1-8的比较,除HPA-3具有明显不同外（P＜0.05）,其余均相似（P＞0.05）;与美国黑人进行HPA1-5的比较,HPA-1、-2、-5具有明显的差异（P＜0.05）;与英国人进行HPA1-11的比较,HPA-1、-5具有明显的不同（P＜0.05）.结论：北方地区中国人群HPA-2、-3、5、-15系统具有多态性,且HPA抗原分布不配合比率较高,这必然造成免疫暴露的机会增加,提示在临床上可能具有重要的免疫学意义.同时,在此次研究数据的基础上建立了邯郸地区血小板基因频率数据库和血小板已知型供者库.     

广州地区无偿献血者HPA-1—6,15基因分型及频率调查

目的研究人类血小板基因多态性,为人类群体遗传学研究及临床输血实践提供重要数据和依据。方法通过PCR-SSP方法对广州地区706名无偿献血者的HPA1—6,15系统进行基因分型,并统计其频率。结果706份样本中HPA-3和-15基因型的杂合程度最高,其a/a、a/b、b/b的频率分别为HPA-3:0.2918、0.4830、0.2252;HPA-15:0.2691、0.5170、0.2139,不配合率较高,均达到35%以上。HPA-1、-2、-4、-5系统均以a/a纯合子为主,a基因的频率范围为0.9583—0.9993,且均未发现b/b纯合子。1b、4b的基因频率很低,分别为0.0028和0.0007。本地区的HPA-1a与中国北方、英国白人、美国黑人有统计学差异(P<0.05)。HPA-2与中国南方、北方、美国黑人和日本人有统计学差异(P<0.05);HPA-5与英国白人和美国黑人存在统计学差异(P<0.05)。HPA-6频率分别为0.9575,0.0397,0.0028。结论本研究对广州地区HPA献血员的筛查可为建立HPA供者库和对探讨由HPA引起的免疫性疾病的预防和治疗提供相关数据和研究手段。     

Genotyping of Eight Human Platelet Antigen Systems in Serbian Blood Donors: Foundation for Platelet Apheresis Registry

IntroductionThe aim of this study was to investigate the allele and genotype frequencies of 8 human platelet antigen (HPA) systems among blood donors from the Blood Transfusion Institute of Serbia and to compare them with published studies. These data would be useful to establish the basis for a platelet apheresis donor registry.Material and MethodsSeventy-two unrelated male platelet apheresis/blood donors from Serbia were typed for 8 HPA systems (HPA-1 to HPA-6, HPA-9, and HPA-15) via the FluoGene method, based on polymerase chain reaction-sequence-specific amplification (PCR-SSP; PCR using sequence-specific primers) with fluorometric signal detection. Allele and genotype frequencies were estimated by direct counting and compared to the expected genotype frequencies according to the Hardy-Weinberg principle. The transfusion mismatch probability was calculated for every HPA specificity.ResultsThe allele frequencies were: HPA-1a, 0.868; HPA-1b, 0.132; HPA-2a, 0.917; HPA-2b, 0.083; HPA-3a, 0.611; HPA-3b, 0.389; HPA-5a, 0.903; HPA-5b, 0.097; HPA-9a, 0.993; HPA-9b, 0.007; HPA-15a, 0.472; and HPA-15b, 0.528. For HPA-4 and HPA-6 only allele a was detected.DiscussionThe HPA allele frequencies of European populations showed no significant differences in comparison with our results. Statistically significant differences were revealed in comparison with some populations of non-European origin. In the tested donors no HPA-2 bb genotype was detected, but we found 1 donor with the rare HPA-9b allele. The biggest transfusion mismatch probability in the Serbian population is for systems HPA-15 (37.4%) and HPA-3 (36.2%), which means that more than a third of random transfusions could cause mismatch in these systems. This study was enabled by the introduction of molecular HPA typing, and it provides initial results of the HPA allele and genotype frequencies in the population of blood donors in Serbia. They will be used to provide a compatible blood supply on demand for treating patients with alloimmune thrombocytopenic disorders. The successful implementation of PCR-SSP with fluorometric signal detection could be further complemented in the future by the introduction of high-throughput methods, which will largely depend on the available financial resources.     

PCR with sequence-specific primer-based simultaneous genotyping of human platelet antigen-1 to -13w

BACKGROUND: Accurate human platelet antigen (HPA) typing is important for patients with diagnosis of alloimmune thrombocytopenic syndromes and provision of HPA-matched blood components for these patients. STUDY DESIGN AND METHODS: Thirteen sequence-specific primers (SSPs) designed on the basis of known published polymorphisms for HPA-1 to HPA-13w, respectively, were employed for simultaneous HPA genotyping. All PCR amplifications were carried out with identical cycling conditions in 96-well plates containing primer mixtures. A total of 300 blood samples from unrelated volunteer donors in Taiwan were included in the study. RESULTS: All primers had specific amplification products. The typing results were available within 4 hours each time for up to four blood samples tested. Among the 13 HPAs, HPA-3 had the greatest heterozygosity with a gene frequency of 0.3267, 0.4967, and 0.1767 for HPA-3a/HPA-3a, HPA-3a/HPA-3b, and HPA-3b/HPA3-b, respectively. For the remaining 12 HPAs, the predominance of a/a homozygosity was noted for HPA-1, -2, -4, -5, and -6, with a frequency ranging from 0.9200 to 0.9967. The frequency of a/a homozygosity was 1.0000 for HPA-7w to -13w, except for HPA-10w, for which one case was observed to be HPA-10aw/HPA-10bw heterozygous. Excluding HPA-3, b/b homozygosity was noted in only one case (HPA-6b/HPA-6b). The prevalence rates of HPA-1 to -13w in this study were consistent with previous reports using different methods. CONCLUSION: An extended, streamlined PCR-SSP protocol for simultaneous genotyping of HPA-1 to HPA-13w was established. This allows fast and reliable diagnosis of alloimmune thrombocytopenia, and is readily applicable to large-scale genetic population studies.     

Frequency of human platelet antigens among blood donors in northeastern Thailand

BACKGROUND: Platelet transfusions have been widely used in Thailand, but little is known about the phenotyping of human platelet antigens. STUDY DESIGN AND METHODS: Whole blood was collected from 483 blood donors for preparation of platelets. An improved mixed passive hemagglutination assay was used for this study. RESULTS: Frequencies demonstrated were 100 percent for HPA-1a (PlA1), 15.94 percent for HPA- 2b (Siba), 60.25 percent for HPA-3a (Baka), 98.76 percent for HPA-4a (Yukb), 1.86 percent for HPA-4b (Yuka), 5.38 percent for HPA-5b (Br(a)), and 97.72 percent for Naka. CONCLUSION: HPA-1a was found in 100 percent of Thais, which is the same frequency as in other Asian populations but somewhat different from that in whites (97.9%). Therefore, HPA-1a will not cause neonatal alloimmune thrombocytopenia or post-transfusion purpura in Thais. According to the frequencies of HPA-2b, HPA-3a, HPA-4a, HPA-4b, HPA-5b, and Naka antigens, they may induce neonatal alloimmune thrombocytopenia, posttransfusion purpura, and platelet refractoriness in Thais.     

应用PCR—SSP法分析中国人血小板抗原基因型频率

本研究建立了在同一PCR反应条件下同时检测人血小板抗原（human platelet antigen,HPA）系统HPA-1到HPA-5的PCR-SSP检测法。应用该方法分析了110例健康献血员的HPA-1到HPA-5的基因型,并以此为依据推算了中国人HPA-1到HPA-5各亚型的基因频率。结果表明HPA-1a和HPA-1b的基因频率分别为0.91和0.09,HPA-2a和HPA-2的基因频率分别为0.86和0.14,HPA-3a和HPA-3b的基因频率分别为0.60和0.40,HPA-4a和HPA-4b的基因频率分别为0.92和0.08,HPA-5a和HPA-5b的基因频率分别为0.85和0.15。结论：基因组DNA的血小板抗原PCR-SSP分型法切实可行,可广泛应用于临床血小板抗原的分型。     

人类血小板抗原1—16基因与血小板输注无效风险研究

目的探讨HPA-1—16基因多态性分布与血小板输注无效相关性。方法应用PCR-SSP法对上海地区268名汉族人群行HPA-1—16基因检测;应用ELISA法对49名反复输血的恶性血液病患者行血小板抗-HLA-Ⅰ与抗-HPA筛查试验。结果上海地区汉族人群HPA-1—16系统中,HPA-1—6,15系统等位基因频率1a=0.9889,1b=0.0111,2a=0.8881,2b=0.1119,3a=0.5989,3b=0.4011,4a=0.9963,4b=0.0037,5a=0.9907,5b=0.0093,6a=0.9832,6b=0.0168,15a=0.6418,15b=0.3582,均呈多态性分布;其余HPA-7—14,16系统等位基因均呈单线性分布。HPA-1,2,4—6,15系统主要以aa纯合子基因型频率分别为0.9776,0.7799,0.9925,0.9813,0.9664,0.4328。在HPA-2、3、15系统中出现bb纯合子基因型,其频率均为0.0037,0.1530,0.1492外,其余系统均未出现bb纯合子基因型。另外,在HPA-1—6,15系统中出现ab杂合子基因型,其频率分别为0.0224,0.2164,0.4963,0.0075,0.0187,0.0336,0.4180,以HPA-3杂合度最高,其次次序为HPA-15、HPA-2。在随机输血中,HPA不合发生率以HPA-3为最高(0.3650),其次分别为HPA-15(0.3541)、HPA-2(0.1790)。49名反复输血的恶性血液病患者中,有61.22%(30名)输血后相继出现抗-HLA-Ⅰ,而始终未检出抗-HPA。结论上海地区汉族人群血小板输注无效的主要原因是抗-HLA-Ⅰ所致;只需检测供者与受(患)者的HPA-2、-3、-15基因相合,就可基本达到血小板匹配性输注。     

海南黎族人血小板1—17抗原基因与随机输血不配合率研究

目的调查海南岛黎族人群血小板抗原(HPA)-1—17等位基因多态性及其特点,评估其在随机输血中血小板输注无效的风险。方法采用PCR-SSP方法对海南岛180名黎族人群做HPA-1—17基因分型检测>计算各系统对偶抗原不配合率。结果在海南黎族人群的HPA-1—17系统中,呈多态性分布的等位基因及其频率为HPA-2a(0.9972)、2b(0.0028),HPA-3a(0.4889)、3b(0.5111),HPA-5a(0.9667)、5b(0.0333),HPA-6a(0.9972)、6b(0.0028),HPA-15a(0.4250)、15b(0.5750);其余HPA-1、4、7—14、16、17等位基因均呈单线性分布。在HPA-3、15等位基因中出现bb纯合子基因型,频率分别为0.2834和0.3667;其余系统均未见bb纯合子基因型。随机输血中,海南岛黎族人群HPA不配合的发生率依次为:HPA-3(37.49%)、-15(36.93%)和-5(6.23%)。结论揭示了海南岛黎族人HPA-1—17基因型和等位基因频率的分布及特点;立足人群的随机血小板输注,只需检测供、受者HPA-2,-3、-5和-15基因相合,就可基本达到血小板匹配性输注。     

Platelet alloantigen frequencies in Amazon Indians and Brazilian blood donors

The frequencies of human platelet-specific alloantigens (HPAs) vary between different ethnic groups, and genotyping using DNA techniques has been preferred over immunophenotyping methods for population studies. Using a polymerase chain reaction with allele-specific primers (PCR-ASP) method, we determined the allelic polymorphisms of five HPA systems among 174 unrelated individuals of two different Brazilian ethnic groups including Amazon Indians (n = 95) and blood donors (n = 79). Comparison of the calculated gene frequencies of the two alleles of HPA-1, -2, -3, -4 and -5 systems for Amazon Indians and Brazilian blood donors showed that gene frequencies obtained for the two alleles of HPA-1 (P<0.001), HPA-2 (P = 0.001) and HPA-5 (P<0.001) were significantly different between the two groups of individuals. All natives tested carried the HPA-2a and the HPA-5a alleles, but the HPA-1b and HPA-4b alleles are absent from the Indian population. It was also observed that all blood donors carried the HPA-1a, HPA-4a and HPA-5a alleles. In conclusion, the present data indicate differences in the frequency of the HPA systems between Amazon Indians and Brazilian subjects who present a high rate of racial admixture. While the frequencies of the HPA-1 and HPA-5 genes seen in Amazon Indians are similar to those reported for Oriental populations, the frequencies of the HPAs alleles in Brazilian blood donors are comparable to those reported for populations in North America and Europe.     

血小板谱抗原的建立及其在鉴定血小板特异性抗体中的应用

目的 建立血小板谱抗原,鉴定引起血小板输注无效和新生儿血小板减少性紫癜的血小板特异性抗体,为血小板血型研究和临床治疗提供依据。方法根据中国人群人类血小板同种抗原(HPA)-1-HPA-16等位基因频率分布资料,利用聚合酶链反应-序列特异引物(PCR-SSP)技术对O型血小板供者进行HPA-1-HPA-6、HPA-15分型,筛选合适的供者,组成血小板谱抗原。通过建立的血小板谱抗原,利用简易致敏红细胞血小板血清学技术(SEPSA)鉴定同种免疫反应产生的血小板抗体的特异性。结果从O型血小板供者中筛选出11名供者,建立了血小板特异性抗体鉴定谱抗原。其可鉴定HPA-1-HPA-6,HPA-15抗体的特异性。在所筛检1 120份样本中,有3例患者检出HPA抗体,其中HPA-4b(Penb)抗体1例,HPA-15a(Govb)抗体2例。结论通过血小板谱抗原鉴定血小板抗体的特异性,对提高临床输注血小板的安全性和有效性,以及预防新生儿血小板减少性紫癜有积极的意义.     

Frequency distribution of antigens in the human platelet antigen-1 system in the western Indian population

BACKGROUND: Neonatal alloimmune thrombocytopenic purpura (NAITP) occurring because of fetomaternal incompatibility in the human platelet antigen-1 (HPA-1) system is increasingly being detected worldwide. Several studies have reported the frequency and distribution of HPA-1 alleles in different countries and ethnic populations. A paucity of data regarding the frequency of the antigens in the HPA-1 system in the Indian population prompted an undertaking of this study. The molecular method of genotyping the platelet antigens is preferred to serology. It will enable future prenatal diagnosis in mothers suspected to have NAITP so that they can be managed better. STUDY DESIGN AND METHODS: Five hundred six unrelated subjects were screened for the alleles in the HPA-1 system, of which 185 were healthy males and 321 were females. DNA was extracted from the peripheral blood WBCs of these subjects, followed by PCR amplification and agarose gel electrophoresis of the PCR-amplified products. RESULTS: Four hundred two out of 506 subjects (79.44%) were found to be homozygous for HPA-1a. Ninety-nine subjects (19.57%) were heterozygous HPA-1a/HPA-1b, and five subjects out of 506 (0.99%) were homozygous for HPA-1b. CONCLUSION: Homozygosity for HPA-1b exists in the Indian population at a frequency of 0.99 percent, whereas homozygosity for HPA-1a is present in approximately 79 percent of the population. Hence, 0.98 x 0.79 of the females (0.77%) in the reproductive age group are likely to be pregnant with an HPA-1a-positive fetus, leading to a setting in which NAITP might develop. The development of NAITP also depends on the HLA type of the mother; nevertheless, the number of pregnancies in which the fetus is at risk for NAITP in India is quite significant.