中华(上海)骨髓库北方人群HLA多态性调查

调查中华(上海)骨髓库北方人群HLA多态性及其频率分布特征。用微量淋巴细胞毒试验检测11995名无关供者HLA-A、B抗原,并用PCR-SSP和反向PCR-SSOP技术对疑难标本进行复检。计算其中3 736名北方人群 HLA-A、B的抗原频率、基因频率和HLA-A、B位点单倍型频率、连锁不平衡参数。调查中共检出A位点抗原26种,B位点抗原54种,最常见HLA-A、B抗原包括A2,A11,A24,A30,A33,B13,B46,B51,B58,B60,B61,B62等。连锁不平衡参数大于0.0005的单倍型有40多种,最常见的单倍型有A2-B46,A30-B13,A33-B58等。结果显示中华(上海)骨髓库北方人群HLA多态性有自身特点,频率分布介于南、北汉族之间。     

Distribution of human leukocyte antigen alleles and haplotypes in Oroqen and Ewenki nationality minority in Inner Mongolia Autonomous Region of China

The frequencies of the human leukocyte antigen alleles HLA-A,-B, DRB1 and the A-B, A-DRB1, B-DRB1, A-B-DRB1 haplotypes were investigated through means of PCR-based reverse line-strip sequence specific oligonucleotide hybridization on 108 Oroqen and 104 Ewenki nationality unrelated healthy individuals from the Inner Mongolia Autonomous Region of China. A total of thirteen different HLA-A alleles, 21 different HLA-B alleles and 13 different HLA-DRB1 alleles were detected in the Oroqen ethnic group and the most frequent HLA alleles found were A*24(35.65%), B*15(17.92%), and DRB1*09(17.59%), respectively. The common HLA-A-B-DRB1 haplotypes were A*24-B*40-DRB1*09(5.09%), A*24-B*48-DRB1*12(2.78%) and A*24-B*51-DRB1*04(2.78%); and the HLA-A*33-B*58, A*30-B*13, A*01-B*37, A*33-DRB1*03, A*01-DRB1*10, A*30-DRB1*07, B*37-DRB1*10, B*58-DRB1*03, B*38-DRB1*08, B*13-DRB1*07 were significant positive linkage disequilibrium in the Oroqen nationality group. In total, 14 different HLA-A alleles, 27 B alleles and 12 DRB1 alleles were found in Ewenki nationality group, and the most frequent HLA alleles found were A*24(24.49%), B*40(17.35%), and DRB1*04(14.80%), respectively. The common HLA-A-B-DRB1 haplotypes were A*33-B*58-DRB1*03(6.25%), A*01-B*51-DRB1*11(2.88%) and A*24-B*40-DRB1*09(2.88%); the HLA-A*33-B*58, A*29-B*44, A*03-B*52, A*33-DRB1*03, A*29-DRB1*07, A*24-DRB1*09, B*58-DRB1*03, B*08-DRB1*03, B*46-DRB1*09 were significant positive linkage disequilibrium in Ewenki nationality group. The distribution of HLA A,-B, DRB1, alleles haplotypes frequencies and phylogenetic tree indicated that the Oroqen and Ewenki population groups belongs to northern group of China, together as a group cluster.     

Distribution of HLA class I alleles and haplotypes in Korean.

The antigen (phenotype), gene (allele) and haplotype frequencies of HLA class I were analysed in 4,622 Koreans. With allele frequencies of over 0.05, the most frequent HLA-A,-B and -C antigens were A2, A24, A33, A11, A26, A31; B62, B51, B44, B54, B61, B35, B58, B60; Cw3, Cw1, Cw4, Cw7. Of these A2, A24, Cw1 and Cw3 were present in very high frequencies, respectively (0.3211, 0.2200, 0.2204, and 0.3737). The most common haplotypes with frequencies larger than 0.02 were A2-Blank, A33-B44, A33-B58, A11-B62, A24-B51, A24-B54, A2-B27, B54-Cw1, B58-Cw3, B51-Blank, B61-Cw3, B62-Cw4, B35-Cw3, B44-Blank, B60-Cw3, B27-Cw1, A2-Cw3, A2-Cw1, A24-Cw1, A33-Cw3, A26-Cw3, and A11-Cw4. A significant negative linkage disequilibrium was found for the haplotypes of A2-B7, A2-B44, A2-B58, A24-B13, A24-B27, A33-B54 and A33-B62, of which frequencies were larger than 0.003. The B-C and A-C haplotypes which showed the significant negative linkage disequilibrium were B44-Cw1, B51-Cw1, B44-Cw3,B62-Blank, A2-Cw4, A2-Blank, A11-Cw3, A11-Blank and A33-Cw1 and had frequencies higher than 0.01. The findings presented here could be used per se to estimate the populational relationships or as the control data for HLA-disease investigation. Furthermore they could provide the scope for the definition of new antigens.     

HLA haplotypes in Koreans based on 107 families

Abstract: There are marked differences in the distribution of HLA haplotypes among different populations, and multilocus HLA haplotypes can best be studied by family analysis. In the present study, 107 Korean families were analyzed for HLA-A, B, C, DR, and DQ antigens and haplotypes. Allele frequencies of more than 10% for class I antigens were A2, A24, A33, B44, B62, Cw1, Cw7, Cw9, Cw10, and C blank (CBL) and those for class II antigens were DR4, DR8, DR13, DR15, DQ1, DQ3, DQ4 and DQ7. In the analysis of HLA haplotypes, 18 kinds of A-B-DR and 11 kinds of A-C-B-DR-DQ haplotypes occurred at frequencies of more than 1%, comprising 34% and 24% of the total theoretical haplotypes, respectively. The five most common A-B-DR haplotypes were exclusively related with the five most common A-C-B-DR-DQ haplotypes (frequency>2%). These remarkably conserved five-locus haplotypes in Koreans were A33-CBL-B44-DR13-DQ1 (5.4%), A24-Cw7-B7-DR1-DQ1 (3.5%), A33-Cw7-B44-DR7-DQ2 (3.0%), A33-Cw10-B58-DR13-DQ1 (2.3%), and A30-Cw6-B13-DR7-DQ2 (2.3%). Comparison of the distribution of A-B-DR haplotypes among East Asian populations revealed that Koreans are closest to Japanese, but show a higher degree of polymorphism in the distribution of HLA haplotypes compared to Japanese. The results obtained in this study will be useful as basic data on Koreans for anthropology and organ transplantation.     

Distribution of HLA gene and haplotype frequencies in Taiwan: a comparative study among Min-nan, Hakka, Aborigines and Mainland Chinese

A total of 8,497 blood samples were typed for HLA-A, B, DR and DQ. Of these, 7,137 Min-nan, 714 Hakka, 535 Mainland Chinese (152 from North China, 211 from Middle China, and 172 from South China) and 111 Aborigines were randomly selected from Tzu Chi Taiwan Marrow Donor Registry (TCTMDR). Differences in HLA gene and antigen frequencies have been observed between various ethnic groups of the Chinese population in Taiwan. The phylogenic tree shows Taiwan Aborigines and Javanese cluster together; Min-nan shares a common cluster with Hakka, Southern Hans and Thai; and Northern Hans shares a cluster with Middle Hans. The separation between Northern/Middle and Southern Chinese Hans support the idea that Northern and Southern Chinese have different genetic background. Aborigines appeared to be quite distinct in the distribution of a majority of the class I and class II antigens. High frequency of HLA-A24 (60.4%) and relatively restricted HLA polymorphisms are noted in Aborigines. The HLA haplotypes with high frequency in Aborigines included A24-B60-DRB1*04, A24-B60-DRB1*14, A24-B48-DRB1*04, and A24-B48-DRB1*14, which are different from the other ethnic groups. Although the phylogenic tree separates Aborigines and Han Chinese populations, 4 out of 20 most common HLA-A, -B, and -DR haplotypes presented in both Aborigines and Han Chinese may reflect an ancient common origin or intermixture between early settlers of Han Chinese and Taiwan Aborigines. The results in this study are essentially a summary of the observed gene/haplotype frequencies and differences among various ethnic groups in Taiwan.     

HLA-A*02 allele frequencies and haplotypic associations in Koreans

We have investigated the frequencies of HLA-A*02 alleles and their haplotypic associations with HLA-B and -DRB1 loci in 439 healthy unrelated Koreans, including 214 parents from 107 families. All of the 227 samples (51.7%) typed as A2 by serology were analyzed for A*02 alleles using polymerase chain reaction (PCR)-low ionic strength-single-strand conformation polymorphism (LIS-SSCP) method. A total of six different A*02 alleles were detected (A*02 allele frequency 29.6%): A*0201/9 (16.6%), *0203 (0.5%), *0206 (9.3%), *0207 (3.0%), and one each case of *0210 and *02 undetermined type. Two characteristic haplotypes showing the strongest linkage disequilibrium were A*0203-B38-DRB]*1502 and A*0207-B46-DRB1*0803. Besides these strong associations, significant two-locus associations (P<0.001) were observed for A*0201 with B61, DRB1*0901 and DRB1*1401, and for A*0206 with B48 and B61. HLA haplotypes carrying HLA-A2 showed a variable distribution of A*02 alleles, and all of the eight most common A2-B-DR haplotypes occurring at frequencies of > or =1% were variably associated with two different A*02 alleles. These results demonstrate that substantial heterogeneity is present in the distribution of HLA-A*02 alleles and related haplotypes in Koreans.     

Study of HLA system in a Mataco population:

A search for antigens of the HLA system has been carried out in 53 Mataco Indians of Argentina living in a geographically isolated area in the northeast of the country. Samples were mostly collected from adults of both sexes who were not directly related.
Lymphocyte typing was performed using the microcytotoxicity technique of NIH. 118 sera specific for 15 antigens of the first HLA locus, 22 antigens of the second and 6 of the third were used.
The most frequently found alleles were HLA-A28, Aw31 and A2 for the first locus; B15 and B40 for the second; and Cw3 and Cw4 for the third.
In addition to previously published investigations on South American Indians, our typing work shows a remarkable homogeneous gene pool and a restricted range of polymorphism; therefore, a further set of haplotypes rendered us also restricted. The most frequent haplotypes that showed a significant statistical linkage desequilibrium were: A2-Cw4, A28-Bx, A2-Cw3, Aw31-Bw16, Aw24-Cw3, B15-Cw3, Bw16-Cw3 and A28-B5.
Some of these haplotypes have also been found in other indian populations.     

A physical linkage map of HLA-A, -G, -7.5p, and -F

The class I region of the human leukocyte antigen (HLA) complex includes genes encoding the classical transplantation antigens (HLA-A, -B, -C), at least three nonclassical class I genes (HLA-E, -F, and -G), and many class I pseudogenes (including HLA-7.5p). We have used probes from DNA within or flanking the HLA -A, -F, -G, and -7.5p genes to construct a physical linkage map that places the HLA-F, -G, and -7.5p loci in order with respect to HLA-A. The map was constructed using clamped homogeneous electric field pulsed-field gel electrophoresis. DNA was isolated from LCL 721 (A1:B8, A2:B5), a human Epstein-Barr virus-transformed lymphoblastoid cell line (LCL), and from two gamma-irradiation-induced mutants of LCL 721 lacking complementary class I haplotypes. The physical linkage data place HLA-G closest to HLA-A and place HLA-7.5p between HLA-G and HLA-F. The map constructed supports a maximum distance of 490 kilobases between HLA-A and HLA-F.     

The effect of parental HLA compatibility on the expression of paternal haplotypes in offspring

The compatibility of HLA-A,-B expression between mother and offspring was examined in 410 families serologically tissue typed within a single transplant lab from 1972 thru 1982. The study group included 410 mothers of 1719 children (range 2–13/mother), with 352 one-father and 58 multiple-father families. There were seven cases of monozygous twins and seven cases each of maternal and paternal allelic recombination. The degree of haplotype matching between the oldest offspring and subsequent siblings was within the expected range of distribution. The number of maternal HLA-A,-B antigens matched or mismatched with paternal antigens of the offspring did not show a significant difference between early born or late born siblings either in one-father or multiple-father families. In addition, where the mother showed significant sensitization to paternal HLA-A,B antigens there was no apparent selection against the incompatible paternal HLA antigens or associated haplotypes in subsequent offspring. These data suggest that maternal HLA compatibility with the father is not a significant selective factor in determining the expression of paternal haplotypes in offspring.     

Polymorphism of HLA-A, -B, -DRB1, -DQA1 and -DQB1 haplotypes in a Croatian population.

We describe for the first time extended haplotypes in a Croatian population. The present study gives the HLA-A, -B, -DRB1, -DQA1 and -DQB1 allele and haplotype frequencies in 105 families with at least two offspring. All individuals were studied by conventional serology for HLA class I antigens (A and B), while class II alleles (DRB1, DQA1, DQB1) were typed using the PCR-SSOP method. HLA genotyping was performed by segregation in all 105 families. For extended haplotype analysis, 420 independent parental haplotypes were included. Fourteen HLA-A, 18 HLA-B, 28 DRB1, 9 DQA1 and 11 DQB1 alleles were found in the studied population. Most of the DRB1 alleles in our population had an exclusive association with one specific DQA1-DQB1 combination. This strong linkage disequilibrium within the HLA class II region is often extended to the HLA-B locus. A total of 10 HLA-A, -B, -DRB1, -DQA1, -DQB1 haplotypes were observed with a frequency 相似文献   

Genetic variation and hitchhiking between structurally polymorphic Alu insertions and HLA-A, -B, and -C alleles and other retroelements within the MHC class I region

We investigated structurally polymorphic Alu insertions (POALINs) at five loci in the major histocompatibility complex (MHC) class I genomic region to determine their allele and haplotype frequencies and associations with the human leukocyte antigen (HLA)-A, -B, and -C genes in three populations, the Australian Caucasians, Japanese, and African Americans. The POALINs varied in allelic frequency between 0% and 42.3% with significant differences between populations at three of the five loci. The linkage disequilibrium (LD) between Alu insertions and the HLA-A, -B, or -C alleles and previously published polymorphic retroelements (four SVA and human endogenous retrovirus type 9 (HERVK9) loci) within the class I region of the MHC were calculated in pairwise analyses of haplotypes to show strong allelic associations and possible crossing-over events between some loci. Each POALIN was in significant LD with a variety of HLA-A, -B, or -C two-digit alleles probably as a result of hitchhiking. The POALINs helped to further stratify the HLA-A:B:C haplotypes into different POALIN:HLA-A:B:C haplotype frequencies. Of the multilocus haplotype analyses, the seven- and eight-locus haplotypes showed the largest number of differences between the populations, and fewer matched haplotypes between populations that ranged, for example, from 49% for HLA-B:HLA-A haplotypes to 7% for AluMICB:HLA-B:HLA-C:AluTF:AluHJ:HLA-A:AluHG:AluTF haplotypes in the Japanese. This comparative study of multilocus POALINs in the HLA class I region of three ethnic populations shows that POALINs alone or together with the HLA class I alleles and other retroelements are informative ancestral markers for assessing the interrelationship of HLA class I haplotype lineages, LD, and genetic diversity within the same and/or different populations.     

The association and linkage of the HLA-A2 class I allele with autism

Previous research has revealed associations between autism and immune genes located in the human leukocyte antigen (HLA). To better understand which HLA genetic loci may be associated with autism, we compared the class I HLA-A and -B alleles in autistic probands with case control subjects from Caucasian families. The frequency of HLA-A2 alleles was significantly increased in autistic subjects compared with normal allelic frequencies from the National Marrow Donors Program (NMDP) (p = 0.0043 after allelic correction). The transmission disequilibrium test for the A2 allele revealed an increased frequency of inheritance for autistic children (p = 0.033). There were no significant associations of autism with HLA-B alleles; however, the A2-B44 and A2-B51 haplotypes were two times more frequent in autistic subjects. The association and linkage of the class I HLA-A2 allele with autism suggests its involvement in the etiology of autism. Possible roles are discussed for the HLA-A2 association in the presentation of microbial antigen within the central nervous system and/or in the establishment of synaptic and neuronal circuits in the developing brain.     

造血干细胞移植56例人类白细胞抗原基因和单倍型分析

背景：收集56例欲行造血干细胞移植的供受者,均为无血缘关系的江西省汉族人群。了解个体的人类白细胞抗原基因型和单倍型。 目的：分析56例造血干细胞移植供受者的人类白细胞抗原基因频率,单倍型频率。 方法：收集56例欲行造血干细胞移植的供受者,均无血缘关系的江西省汉族人群。应用PCR-SSP的方法进行人类白细胞抗原(HLA)-A、B、DRB1基因分型,计算出HLA-A、B、DRB1各位点的基因频率和单倍型频率。 结果与结论：56例供受者测出HLA-A位点等位基因8种,HLA-B位点等位基因19种,HLA-DRB1位点等位基因13种,呈现出丰富的基因多态性。56例供受者两位点共224条等位基因中,A﹡02-B﹡46、A﹡11-B﹡40、B﹡46-DRB1﹡09单倍型的频率高于0.10。有10种A-B单倍型,4种B-DRB1单倍型呈现出显著的连锁不平衡。提示江西省汉族人群人类白细胞抗原基因具有较丰富的基因多态性。     

西北地区汉族人群HLA-A、-B、-DRB1基因座单倍型分析

目的 分析西北地区汉族群体HLA-A、-B和-DRB1基因座等位基因频率和HIA-A-B、B-DRB1和A-B-DRB1单倍型，获得单倍型频率数据。方法 采用序列特异性寡核苷酸探针反向斑点杂交技术对西北地区62个家系和101个无关个体HLA-A、-B和-DRB1基因座进行基因分型，分析HLA单倍型。结果 在西北地区汉族人群中检出15个HLA-A等位基因，28个HLA-B等位基因，13个HLA-DRB1等位基因，A02、A11、A24、B13、B15、1340、DRB1＊04、DRB1＊07、DRB1＊09和DRB1＊15基因频率较高（〉10％），A02（0．3244）、B13（0．1200）和DRB1＊15（0．1400）等位基因频率最高。分析得出HLA-A-B、B-DRB1、A-B-DRB1单倍型分别有122、147和278种，83种A-B-DRB1单倍型有至少两条以上相同的单倍型，占总单倍型数的18．44％（83／450）。A30-B13-DRB1＊07、A02-B46-DRB1＊09、A01-B37-DRB1＊10、A24-B15-DRB＊15、A02-B46-DRB1＊08、A33-B58-DRB1＊03是最常见的单倍型。结论 西北地区汉族群体HLA单倍型多态性较为丰富，等位基因频率和单倍型频率数据可用于骨髓移植供者的选择、法医学亲权鉴定以及人类学研究。     

Expression of HLA class I antigens in transporter associated with antigen processing (TAP)-deficient mutant cell lines

Abstract: Cells lacking expression of the transporter associated with antigen processing (TAP) are deficient in surface HLA class I, yet express reduced levels of HLA-A2 antigen through TAP-independent processing pathways. We have analysed the expression of HLA-A, -B and -C antigens on the 721.174 and T2 TAP-deficient mutant cell lines using a panel of monoclonal antibodies specific for the HLA antigens encoded by the genotype of these cells. Our study has shown the constitutive expression of HLA-Cwl molecules on the cell surface of both T2 and 721.174 cells and has confirmed that HLA-A2 and HLA-B51 are expressed at low levels. Transfection of 721.174 cells with cDNAs encoding TAP1 and TAP2 proteins did not fully restore HLA class I antigen expression on these cells, which appeared to be mainly due to a deficiency in expression of the HLA-B51-associ-ated Bw4 epitope. This suggests that additional antigen-processing genes may be required for optimal generation of HLA-B-binding peptides. Our results indicate that TAP-independent pathways of antigen-processing provide peptides for functional expression of all three classical HLA class I molecules.     

Genetic markers in the Tuvan population of Todja, Siberia

Todja is a secluded region of northern Tuva situated in the Sayany Mountains, Siberia. The aboriginal population of Todja is Tuvan. A total of 128 healthy Tuvans living in Todja were typed for HLA-A, -B and -C antigens and several plasma and erythrocyte protein polymorphisms (Hp, Tf, Gc, ESD, ACP, PGM1, PGD and ADA). The observed frequencies of all 8 blood protein and HLA genotypes were in agreement with Hardy-Weinberg expectations. The most frequent HLA antigens in Todjans are A2 (0.36). A3 (0,24), A9 (0.50), B15 (0.34) and B40 (0.50). HLA haplotypes A2B5, A2B40, A9B15 and A9B40 are most common in this population. The observed frequencies of protein polymorphisms and HLA antigens and haplotypes in Todjans are similar to those of other Mongoloid populations. A comparison of HLA frequencies currently observed in Todjans with those obtained 20 years ago at the same locality showed minor changes attributable to the effect of migration.     

Genetic predetermination of quantitative expression of HLA antigens in platelets and mononuclear leukocytes

In view of the potential functional importance of quantitative expression of HLA antigens, a series of studies were conducted to determine the relative quantities of specific HLA-A and -B antigens expressed in MNLs and platelets of HLA-phenotyped family members and unrelated individuals. An mAb that reacts with a well-defined monomorphic epitope in the α₃ domain of the heavy chains of HLA molecules was developed and used to quantify each HLA-A or -B antigen on western blots of IEF gels. The results of these studies demonstrated that the relative quantities of HLA-A and -B antigens in platelets and MNLs of an individual did not change over time. Further studies showed that the relative quantities of HLA-A and -B antigens for haplotypes shared among the first-degree relatives were always the same and followed Mendelian inheritance. In contrast, the relative quantities of HLA-A and -B antigens for a haplotype shared by unrelated individuals varied significantly. All these findings support the hypothesis that the quantitative expression of HLA antigens is genetically predetermined and may play important roles in determining disease susceptibility and severity. Human Immunology 38, 243–250 (1993)     

B- and T-Cell-Specific Alloantigens in Man

Screening for B-cell-specific antibodies in unabsorbed pregnancy sera preselected for weak reactivity in regular HLA-A, -B, and -C screening yielded a relatively high proportion (35/81) of B-cell-specific antibodies. Most B-cell-specific antibodies react broadly, showing inclusion phenomena suggesting 'cross-reactivity' analogous to that observed in HLA-A and -B serology. In control experiments with T-cell-enriched suspensions three antisera reacted with T cells and not with B cells. These antisera are highly associated with HLA-A2 in the unrelated population and segregate with HLA haplotypes in families and with HLA-A in a family with HLA-A, B recombination, Thus it appears that the human equivalents of Ia antigens may include--in analogy to the murine Ia antigens--B cell- as well as T-cell-specific alloantigens.     

Characteristics of HLA class I and class II polymorphisms in Rwandan women

OBJECTIVE: To define HLA class I and class II polymorphisms in Rwandans. METHODS: PCR-based HLA genotyping techniques were used to resolve variants of HLA-A, B, and C to their 2- or 4-digit allelic specificities, and those of DRB1 and DQB1 to their 4- or 5-digit alleles. RESULTS: Frequencies of 14 A, 8 C, and 14 B specificities and of 13 DRB1 and 8 DQB1 alleles were >/=0.02 in a group of 280 Rwandan women. These major HLA factors produced 6 haplotypes extending across the class I and class II regions: A*01-Cw*04-B* 4501-DRB1*1503-DQB1*0602 (A1-Cw4-B12- DR15 - DQ6), A * 01 - Cw * 04 - B * 4901 -DRB1 * 1302-DQB1*0604 (A1-Cw4-B21-DR13-DQ6), A*30 - Cw*04 - B*15 - DRB1*1101 - DQB1*0301 (A19-Cw4-B15-DR11-DQ7), A*68-Cw*07-B* 4901-DRB1*1302-DQB1*0604(A28-Cw7-B21- DR13 - DQ6), A*30 - Cw*07 - B*5703 - DRB1* 1303-DQB1*0301(A19 - Cw7 - B17 - DR13 - DQ7), and A*74-Cw*07-B*4901-DRB1*1302-DQB1* 0604 (A19-Cw7-B21-DR13-DQ6), respectively. Collectively, these extended haplotypes accounted for about 19% of the total. Other apparent class I-class II haplotypes (e.g., Cw*17-B*42-DRB1*0302-DQB1*0402, Cw*06- B*58-DRB1*1102-DQB1*0301, and Cw*03- B*15-DRB1*03011-DQB1*0201) did not extend to the telomeric HLA-A locus, and other 3-locus class I haplotypes (e.g., A*68-Cw*04-B*15, A*74-Cw*04-B*15, and A*23-Cw*07-B*4901) completely or partially failed to link with any specific class II alleles. DISCUSSION: Frequent recombinations appeared to occur between the three evolutionarily conserved HLA blocks carrying the class I and class II loci. The HLA class I profile seen in Rwandans was not directly comparable with those known in the literature, although the class II profile appeared to resemble those in several African populations. These data provide additional evidence for the extensive genetic diversity in Africans.     

Allotyping for HLA class I using plasma as antigen source

Immunoadsorption of soluble HLA class I antigens onto immunobeads, one-dimensional iso-electric focusing of these proteins and subsequent immunoblotting allows a biochemical identification of HLA class I allotypes. The distinct protein bands can be clearly attributed to particular HLA antigens and are comparable to those observed after detergent solubilization of membrane-bound HLA antigens. Segregation analysis showed that the biochemically detected pattern of soluble class I gene products followed Mendelian inheritance. However, antigens such as HLA-A1, -A2, -B8, and -B51 were not always clearly detectable, a phenomenon attributable to either different plasma concentrations of these HLA antigens or variable affinity of the monoclonal antibody used to capture class I antigens. These results show that in principle allotyping of HLA class I using plasma as the antigen source is feasible, but with the limitation that some antigens may not be easily detected in some individuals.