June 2002
Volume 43, Issue 6
Biochemistry and Molecular Biology  |   June 2002
Amino Acid Residue 67 (Isoleucine) of HLA-DRB Is Associated with POHS
Author Affiliations
  • Jenny V. Ongkosuwito
    From the Department of Ophthalmology, Academic Medical Centre Amsterdam, Amsterdam, The Netherlands; the
  • Marcel G. J. Tilanus
    Departments of Molecular and Immunopathology and
  • Allegonda Van der Lelij
    Ophthalmology, University Medical Centre Utrecht, Utrecht, The Netherlands; the
  • Mary J. van Schooneveld
    Ophthalmology, University Medical Centre Utrecht, Utrecht, The Netherlands; the
  • Martine J. Jager
    Department of Ophthalmology, Leiden University Medical Center, Leiden, The Netherlands; and the
  • Erik H. Rozemuller
    Departments of Molecular and Immunopathology and
  • Marc D. de Smet
    From the Department of Ophthalmology, Academic Medical Centre Amsterdam, Amsterdam, The Netherlands; the
  • Maria S. A. Suttorp-Schulten
    Department of Ophthalmology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
Investigative Ophthalmology & Visual Science June 2002, Vol.43, 1725-1729. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Jenny V. Ongkosuwito, Marcel G. J. Tilanus, Allegonda Van der Lelij, Mary J. van Schooneveld, Martine J. Jager, Erik H. Rozemuller, Marc D. de Smet, Maria S. A. Suttorp-Schulten; Amino Acid Residue 67 (Isoleucine) of HLA-DRB Is Associated with POHS. Invest. Ophthalmol. Vis. Sci. 2002;43(6):1725-1729.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

purpose. To investigate whether presumed ocular histoplasmosis syndrome (POHS) in The Netherlands is associated with HLA-DR2 and HLA-B7, as previously shown in the United States.

methods. Twenty-four Dutch patients with POHS were included in this study. DNA isolated from peripheral blood leukocytes was typed for HLA by a sequence-based method. Associations were statistically determined. The frequencies of HLA alleles in bone marrow of donors listed on the European donor registry was used to represent the distribution in the normal population. Patients were included in the study only when no cells were present in the vitreous at any time and when fundus photographs fit the diagnosis made according to the following criteria: presence of peripapillary atrophy, presence of punched out chorioretinal lesions (histospots), and presence of a submacular scar. After the fundus photographs were judged, the patients were divided into two groups. Group1 contained patients who met all three diagnostic criteria (complete POHS), and group 2 contained patients who met one or two of the criteria (incomplete POHS).

results. Group 1 consisted of 14 patients and group 2 of 10 patients. An association between POHS and HLA-DR2 and -B7 was present, compared with the normal Dutch control subjects. Although significant, the association between the frequency of HLA-DR2 and -B7 of all patients with POHS was less striking than the findings in patients with POHS in the United States. The association with DR2 in patients with incomplete POHS (group 2) was significantly different from that in the group with complete POHS (group 1). According to the defined criteria the association of POHS with HLA-B7 and -DR2 was confined to the incomplete POHS group and was not found in the complete POHS group. Furthermore, analysis of DR at the amino acid level, rather than at the allele level (DR2) showed that amino acid 67 of the DRB1 alleles had the most significant HLA association with POHS, independent of the two groups.

conclusions. POHS in Dutch patients was associated with HLA-B7 and -DR2, but more striking was the presence of isoleucine at position 67 of the HLA-DR molecule.

In uveitis, a constellation of syndromes affecting the pigment epithelium and the inner choroid are known as white-dot syndromes. Among these, POHS is a well-characterized clinical entity. It typically consists of white, atrophic, sharply circumscribed scars (0.2–0.3 disc diameter) scattered throughout the fundus (histoplasmosis spots, or histospots), disciform macular scars, peripapillary scarring, and the absence of active vitreous inflammation. POHS usually occurs in young individuals. When subretinal neovascularization develops in the macular region, it results in permanent loss of vision. Poor vision is present in 50% of affected individuals. 1 Although the characteristics are often used as criteria to diagnose this ocular syndrome, not all patients fulfill all criteria. 
In the United States, POHS is predominantly, but not exclusively, seen in the Midwest, where the fungus Histoplasma capsulatum is endemic. Based on epidemiologic studies in the United States, a correlation between the clinical appearance characteristic of POHS and the presence of this fungus has been established—hence, the name POHS. 2 Previous studies concerning this ocular syndrome in the Netherlands has shown no etiological association between Histoplasma capsulatum and POHS in the Netherlands. 3 Therefore, this infectious agent is unlikely to be responsible for the clinical manifestations observed in European patients with POHS. 
An association of POHS in the United States with HLA-DR2 (of which DR15 is a subgroup) and HLA-B7 has been reported with a frequency of 81% and 77%, respectively. 4 5 This association with both HLA-DR2 and -B7 is explained by the strong linkage disequilibrium between these two genes. Other HLA-B alleles that are in linkage disequilibrium with DR2, such as B27-DR2, have been associated with certain autoimmune diseases, such as ankylosing spondylitis. 6  
With the advent of more refined techniques for HLA typing, it has been possible to link certain disease entities to specific amino acid substitutions at defined positions within the alleles rather than to the individual alleles as a whole. 7 8  
The use of DNA sequencing techniques has facilitated the detailed mapping of binding domains within the HLA class II molecules. For HLA-DRB alleles, amino acid residues located at position, 47, 67, 70, 71, and 86 are essential for peptide binding (antigen) and subsequently for T-cell recognition. 7 8 9 10 11 The purpose of the present study was to determine the HLA association in Dutch patients with POHS and to investigate whether specific loci within the HLA-DRB allele were particularly associated with this syndrome. 
Patients and Methods
Patients with diagnosed POHS were selected from the Ophthalmology department of the University Medical Centre Utrecht and of the Academic Medical Centre Amsterdam. Patients were included only if both fundus photography and data concerning the ophthalmic examination and therapy were available. 
Fundus photographs of 24 patients were judged in a masked fashion after they were mixed with 24 photographs of patients with similar ocular findings, such as acute multifocal posterior placoid epitheliopathy and ocular toxoplasmosis. Photographs were judged by three of the authors (MdS, AvL, MvS), who were not aware of the diagnosis. Patients who met the criteria for POHS were asked to participate in the study and to provide a venous blood sample. All patients were informed about the procedure and signed an informed consent approved by the Committee of Ethics of the University Hospital Amsterdam, according to the tenets of the Declaration of Helsinki. 
Patients were excluded from this study if any sign of ocular inflammation (vitreous cells) was present at any time or if they did not meet the criteria. After inclusion, the following three characteristics were used to further characterize the diagnosis of POHS: the presence of peripapillary atrophy, the presence of punched out peripheral lesions (histospots), and the presence of a macular scar or subretinal neovascularization. 
If all three characteristics were present, the diagnosis was complete POHS. If one or two characteristics were present, the diagnosis was possible POHS. Thus, the following two groups were defined: group 1, complete POHS, defined as having all three characteristics; and group 2, incomplete POHS, defined as having one or two of the characteristics. 
All patients were tested according to the following procedure. DNA was isolated from peripheral blood leukocytes from an EDTA-treated venous blood sample, using a salting-out method according to Miller et al. 12 In short, erythrocytes were lysed using a hypotonic lysis buffer. The lysate was digested with proteinase K in SDS buffer and proteins precipitated by saturated NaCl. The supernatant, containing DNA, was precipitated by adding two volumes of absolute ethanol and washed twice with 70% cold ethanol. DNA was solved in Tris-EDTA buffer and stored at 4°C. 
High-resolution HLA typing was performed by sequence-based typing for HLA-DRB and HLA-A, respectively, as previously described. 13 14 For other loci, the protocols from The 12th International Histocompatibility Workshop were used. 15  
In short, for each HLA locus, specific amplifications were performed by polymerase chain reaction (PCR). Both primers were elongated with templates for the universal M13 forward and reverse sequencing primers for direct sequencing (ABI 373; PE Biosystems, Foster City, CA). Once a sequence had been obtained, sequence data were analyzed with sequencing analysis software (PE Biosystems). Heterozygous positions were assigned with the Hetero program and allele assignments were made with the Allele program. Both are software programs developed for sequence-based typing of HLA genes (PE Biosystems). 16 17  
Statistical analysis was performed as described by Svejgaard et al. 18 For the association of DR types, the Fisher exact test for two-by-two tables was performed. The Bonferroni correction of probability was applied as a correction for the comparisons made (n = 9). For frequency of B7, no other comparisons were performed except with the presence of B7 in the control group. As the control frequency, we used the frequency from the Dutch bone marrow donor registry, as reported by Schipper et al. 19  
Twenty-four patients (18 women and 6 men) with POHS were typed for HLA class I (HLA-A and -B,) and class II (HLA-DRB, -DQB, and -DPB; Table 1 ). In patients 2.3 and 2.5, possible new HLA alleles were identified. Further analysis and cloning is necessary to confirm these findings. 
Patients as a Whole
In our group of patients with POHS HLA-DR15 (a subgroup of HLA-DR2) was found at a frequency of 0.25, significantly higher than in the control group (frequency, 0.137; P < 0.001). The previously observed association between POHS and HLA-B7 was also confirmed, with a frequency of 0.273 (control frequency, 0.148; P < 0.001). No alleles of the other, low-frequency DR2 subgroup, DR16, were identified (Table 2)
The frequency of other alleles present in the patients was not significantly different between patients and the Dutch control (e.g., the frequency of HLA-DR13 was 0.18 in patients with POHS and 0.15 in the Dutch control; χ2 0.73, P = 0.3). No association was found with the HLA-A, DQB, and DPB alleles. For clarity in Table 2 , only statistically significant results were presented. 
Because in our group of patients with POHS the strongest association was found for HLA-DR15 (subgroup of DR2), we analyzed for the presence of specific amino acids in peptide binding (positions 47, 67, 70, 71, and 86) in the DRB alleles. The frequencies were compared with those known frequencies in a large cohort of the Dutch population (Table 3) , estimated from the allele frequencies and assuming the highest frequency of the individual allele types, because no high resolution was available from the control panel. This overestimates the frequency, because some alleles do not have that amino acid. The amino acid isoleucine at position 67 was significantly more frequently detected in patients with POHS than in the Dutch control (P = 0.0003). It was present in almost all patients with POHS. This consequently resulted in a significantly lower presence of phenylalanine at position 67. Some significant differences were noted in positions 70 (arginine was significantly more often present) and 71 (alanine and glutamic acid were significantly more often present), but these were present in very few patients and therefore were not taken into consideration. Analysis of positions 47 and 86 did not reveal any significant differences. Only the results of the analysis of position 47 and 67 are stated in Table 3
As mentioned earlier, to assess the possible role of HLA-DR15 and/ or isoleucine at position 67 in the clinical picture, patients were divided among patients into two groups: group 1 (complete POHS), 14 patients; and group 2 (incomplete POHS), 10 patients. All patients in group 1 had all three clinical characteristics; in group 2, nine patients had two characteristics and one patient had one. 
A significant association of DR15 with group 2 (incomplete POHS) was found (P < 0.0001), whereas this association with group 1 (complete POHS) was not significant (P = 0.9862). Accordingly, as a result of the linkage disequilibrium between HLA-B7 and HLA-DR2, HLA-B7 was also significantly associated with group 2 (P < 0.0001), whereas group 1 showed no significant association (P = 0.3398). 
For isoleucine at position 67 the calculated frequencies were statistically significant in group 1 (P = 0.0002) and group 2 (P = 0.0006) when analyzed individually. No significant difference between the groups and their association with isoleucine at position 67 was seen (Table 3)
Evaluation of individual symptoms (the presence of peripapillary atrophy, histospots, or submacular neovascularization) in groups 1 and 2 did not show an association with HLA-B7-DR15 or isoleucine at position 67. 
In the present study, we showed, as was observed in US patients, an association between presumed ocular histoplasmosis syndrome and HLA-DR2 and -B7. This association in our study sample was much stronger for HLA- DR15 (a subtype of DR2), and more specifically for the presence of an isoleucine at position 67 of the HLA-DRB1 locus. 
Initially, POHS was thought to result from a systemic or ocular infection with H. capsulatum, but the presence of the same clinical entity in Europe and other areas nonendemic for histoplasmosis argues for a multifactorial origin. Studies in the United States have shown an association between HLA-DR2 and -B7. 5 20 However, a known linkage disequilibrium exists between these two genes. 19 The present study shows a stronger association with HLA-DR15 and is probably not only relevant to the European population, but also to the US one. When our patients were divided into two groups (complete and incomplete POHS), according to the presence or absence of all clinical criteria defining the syndrome, the HLA-DR15 association (and in particular HLA-DRB1*15011) was obvious in the incomplete POHS group (P < 0.0001). Such an analysis has not been previously performed, in part because patients have not been so strictly classified according to the presence or absence of all criteria defining the entity known as POHS. The number of patients is limited, making speculation difficult. However, one can envisage that HLA class II is associated with only a portion of the criteria defining the syndrome, explaining why it shows a stronger relationship to the incomplete type. To obtain a complete typing, either external factors or possibly the action of a separate gene or genes is necessary. Indeed, the presence of chorioretinal atrophy in the peripapillary and/or at extrafoveal sites does not necessarily imply a linkage with the process leading to macular scarring or the development of a subfoveal neovascular membrane. 
The present study, by making use of high resolution HLA typing was able to identify a critical amino acid at the peptide-binding locus within the HLA-DRB1 allele. This has not been reported previously in the US population. We specifically found that this syndrome is associated with isoleucine at position 67 of HLA-DRB1. Isoleucine at position 67 was found in almost all patients with POHS, regardless of their HLA-DR2 typing. Other peptide binding sites of the DRB1 allele, which showed statistically significant associations with specific amino acids were positions 70 and 71. However, at these two positions, too few patients showed an association to make it clinically relevant. A study of a larger sample might allow a complete delineation of the peptide binding motif in this population and identify the source of antigenic response. Alternatively, it might identify the importance of protein encoded just outside the HLA locus in the inflammatory process. 
In a recent study, Kobayashi et al. 21 demonstrated that T cells from patients with Vogt-Koyanagi-Harada (VKH) disease recognize tyrosinase-derived peptides. This article appeared shortly after VKH disease was shown to be associated with HLA-DRB1*0405. Tyrosinase was suggested as a possible target of the known binding motif of HLA-DRB1*0405. Their results suggest that tyrosinase, a normal self protein may be involved in the pathophysiology of VKH. 
Disease susceptibility associated with specific class II genes can be the result of linkage disequilibrium with proteins located just outside the HLA locus. In a recent study of patients with multiple sclerosis, in which direct sequencing of exon 2 of the HLA-DRB1 allele was used, disease susceptibility was associated with the presence of specific amino acids at positions 11, 13, and 71. 22 These were all related to HLA-DR2, and no allele-independent residues relevant to antigen binding conferred disease susceptibility, possibly by increasing proinflammatory cytokine secretion or HLA class II expression. Similarly in Behçet disease a recent study has suggested that disease susceptibility relates to HLA-B51 is more closely reflected by its association with major histocompatibility complex class I chain-related genes (MICA). 23 This gene is located near HLA-B and is associated with HLA-B through linkage disequilibrium. 
Our present study was too limited to determine which process is predominant. Isoleucine at position 67 appeared to be independent of the specific HLA-DR2, possibly indicating that it is related to a specific binding motif rather than linked by linkage disequilibrium to an unknown protein. Too few data are available on the other two positions that were identified. In essence, a larger study is needed in which patients with complete and incomplete POHS are studied with advanced genotyping techniques. Such a study would help to answer the question of whether allelic association to DRB1*15011 is based on antigen presentation through a specific peptide determinant or is the result of immune enhancement from a protein located adjacent to the HLA site. If it is related to a specific amino acid–binding motif, the peptides capable of activating the immune process can then be identified. This, in turn, will allow the identification of the putative organism(s) capable of causing the clinical syndrome known as POHS. 
Table 1.
Results of HLA Typing in Patients with POHS
Table 1.
Results of HLA Typing in Patients with POHS
Patient Sex HLA-DRB1 HLA-DRB3 DRB4 DRB5 DQB DPB1 HLA-A HLA-B Total Score
1.1 F 1301 1302 0202,0301 0607,0608 0401,1501 0101,2402 15011,1801 3
1.2 F 0101 1201 0202 0501,03011 0401,0501 02011,— 27053,3503 3
1.3 F 1302 0301,— 0604,— 0401,0402 3001,— 4402,4901 3
1.4 F 0401 15011 0103 01011 0602,0302 0301,0401 2403,3303 44031,15011 3
1.5 F 0101 15011 01011 0501,0602 0401,— 02011,2402 07021,27052 3
1.6 F 0401 0103,— 03011,— 0401,— 02011,2301 4402,4901 3
1.7 M 0101 0701 0103 0501,03032 0401,— 0101,0301 3501,5701 3
1.8 F 1302 0701 0301 0103 0604,— 0301,0401 02011,0301 07021,4001 3
1.9 F 0701 15021 0103 0102 ND 0401,0501 0101,0206 4001,5701 3
1.10 M 0701 12021 0301 0103 03011,03032 0401,— 02011,2407 1502,— 3
1.11 F 0101 0701 01011 0501,0201/0202 0401,1501 0205,2402 0801,4701 3
1.12 F 0404 1001 0103 0501,0302 01011,02012 02011,— 3701,51011 3
1.13 M 0101 15011 01011 0501,0602 0401,0601 0226,0301 07021,— 3
1.14 F 1401 11011 0202 05031,03011 0301,0501 02011,2402 07021,— 3
2.1 F 1301 15011 0101 01011 0602,0603 0301,0402 ND 07021,4402 2
2.2 F 15011 01011,— 0602,0603 0301,0401 02011,0301 07021,— 2
2.3 F 1303 15011 0101 01011 0602,0301 0401,— 02011,31012 5701,AW3new 2
2.4 F 1401 15011 0202 01011 05031,0602 02012,0401 02011,2405 07021,3503 2
2.5 M 0701 15011 01011 01011 0602,0201/0202* 0401,A W1new 0301,31012 44031,— 2
2.6 M 1301 15011 0202 01011 0602,0603 0401,02012 02011,3201 07021,15011 2
2.7 F 0701 1001 0103 0501,0201/0202* 0401,0601 02011,2402 3512,51011 2
2.8 F 0101 0701 01011 0501,0201/0202* 0401,11011 02011,2402 15011,44031 2
2.9 M 0407 0408 0103,— 03011,0304 0401,1001 0301,6802 3503,5001 2
2.10 F 1302 15011 0301 01011 0602,0604 0301,0401 0101,2402 07021,5701 1
Table 2.
Frequency of HLA-DR15 and HLA-B7 Alleles of Patients with POHS Compared with Dutch Control Subjects
Table 2.
Frequency of HLA-DR15 and HLA-B7 Alleles of Patients with POHS Compared with Dutch Control Subjects
Alleles Whole Group (n = 24; 48 alleles) Group 1 (n = 14; 28 alleles) Group 2 (n = 10; 20 alleles) Dutch Control Frequency* (n = 2440)
n Frequency P n Frequency P n Frequency P
DR15 11 0.250 <0.0001 4 0.142 NS 7 0.350 <0.0001 0.137
* 15011 10 0.229 <0.0001 3 0.107 NS 7 0.350 NS
* 15021 1 0.200 NS 1 0.036 NS 0 0.000 NS
B7* 07021 12 0.273 <0.0001 4 0.143 NS 8 0.400 <0.0001 0.148
Table 3.
Frequencies of Residues at Positions 47, 67, 70, and 71 of HLA-DRB1
Table 3.
Frequencies of Residues at Positions 47, 67, 70, and 71 of HLA-DRB1
Residues Whole group (n = 24 patients; 48 alleles) Group 1 (n = 14 patients; 28 alleles) Group 2 (n = 10 patients) Dutch Control Frequency
n Frequency χ2 P n Frequency χ2 P n Frequency χ2 P
47 Tyrosine 25 0.521 0.01 NS 15 0.545 0.05 NS 10 0.500 0.16 NS 0.529
47 Phenylalanine 23 0.479 1.13 NS 13 0.455 0.46 NS 10 0.500 1.93 NS 0.411
67 Leucine 16 0.333 0.82 NS 10 0.357 1.32 NS 5 0.250 0.49 NS 0.390
67 Isoleucine 30 0.625 12.95 0.0003 16 0.571 14.28 0.0002 15 0.750 11.87 0.0006 0.398
67 Phenylalanine 2 0.042 8.01 0.005 2 0.071 7.47 NS 0 0.000 8.48 NS 0.152
70 Arginine 4 0.083 1.59 NS 4 0.154 18.46 <0.0001 0 0.000 5.40 NS 0.054
71 Alanine 12 0.250 8.21 0.004 9 0.346 29.35 <0.0001 3 0.136 0.02 NS 0.142
71 Glutamic acid 8 0.167 1.47 NS 3 0.115 0.06 NS 5 0.227 8.60 0.003 0.124
The authors thank Anne-Wil van der Zwan, Erik Rozemuller, and Sitha Scheltinga for their contribution to this study and the patients for their participation. 
Gass JD, Wilkinson CP. Follow-up study of POHS. Trans Am Acad Ophthalmol Otol. 1972;76:672–694.
Smith RE, Ganley JP. An epidemiological study of presumed ocular histoplasmosis. Trans Am Acad Ophthalmol. 1971;75:994–1005.
Ongkosuwito JV, Kortbeek LM, Van der Lelij A, et al. Aetiological study of the presumed ocular histoplasmosis syndrome in the Netherlands. Br J Ophthalmol. 1999;83:535–539. [CrossRef] [PubMed]
Meredith TA, Smith RE, Braley RE, Witkowski JA, Koethe SM. The prevalence of HLA-B7 in presumed ocular histoplasmosis in patients with peripheral atrophic scars. Am J Ophthalmol. 1978;86:325–328. [CrossRef] [PubMed]
Meredith TA, Smith RE, Duquesnoy RJ. Association of HLA-DRw2 antigen with presumed ocular histoplasmosis. Am J Ophthalmol. 1980;89:70–76. [CrossRef] [PubMed]
Fraile A, Nieto A, Beraun Y, et al. Tumor necrosis factor gene polymorphisms in ankylosing spondilitis. Tissue Antigens. 1998;51:386–390. [PubMed]
Winchester R, Chen Y, Rose S, Selby J, Borkowsky W. Major histocompatibility complex class II DR alleles DRB1*1501 and those encoding HLA-DR13 are preferentially associated with a diminution in maternally transmitted human immunodeficiency virus 1 infection in different ethnic groups: determination by an automated sequence-based typing method. Proc Natl Acad Sci USA. 1995;92:12374–12378. [CrossRef] [PubMed]
McKinney JS, Fu X-T, Swearingen C, Klohe E, Karr RW. Individual effects of the DR11-variable β-chain residues 67, 71, and 86 upon DR(α, β1*1101)-restricted, peptide-specific T cell proliferation. J Immunol. 1994;153:5564–5571. [PubMed]
L’Faqihi FE, Praud C, Yassine-Diab B, et al. Residue 67 in the DR β1*0101 and DR β1*0103 chains strongly influences antigen presentation and DR-peptide molecular complex conformation. Tissue Antigens. 1998;51:10–19. [CrossRef] [PubMed]
Hirayama K, Chen H, Kikuchi M, et al. Glycine-valine dimorphism at the 86th amino acid of HLA-DRB1 influenced the prognosis of postschistomal hepatic fibrosis. J Infect Dis. 1998;177:1682–1686. [CrossRef] [PubMed]
Olson RR, Reuter JJ, McNicholl J, et al. Acidic residues in the DRβ chain third hypervariable region are required for stimulation of a DR (α, β1*0402)-restricted T-cell clone. Hum Immunol. 1994;41:193–200. [CrossRef] [PubMed]
Miller SA, Dyles DD, Polesky HF. A simple salting out procedure for extracting DNA from human nucleated cells. Nucleic Acids Res. 1988;16:1215. [CrossRef] [PubMed]
McGinnis MD, Conrad MP, Bouwens AGM, Tilanus MGJ, Kronick MN. Automated, solid-phase sequencing of DRB region genes using T7 sequencing chemistry and dye-labeled primers. Tissue Antigens. 1995;46:173–179. [CrossRef] [PubMed]
Scheltinga SA, Johnston-Dow LA, White CB, et al. A generic sequencing based typing approach for the identification of HLA-A diversity. Hum Immunol. 1997;57:120–128. [CrossRef] [PubMed]
Tilanus MGJ, Eliaou JF. HLA-sequencing based typing: strategy and overview. Charron D eds. HLA Generic Diversity of HLA Functional and Medical Implication. 1997;1:237–266. EDK Paris.
Rozemuller EH, Bouwens AGM, Bast EJEG, Tilanus MGJ. Assignment of HLA-DPB alleles by computerized matching based upon sequence data. Hum Immunol. 1993;37:207–212. [CrossRef] [PubMed]
Versluis LF, Rozemuller EH, Tonks S, et al. High-resolution HLA-DPB typing based upon computerized analysis of data obtained by fluorescent sequencing of the amplified polymorphic exon 2. Hum Immunol. 1993;38:277–283. [CrossRef] [PubMed]
Svejgaard A, Ryder LP. HLA and disease associations: detecting the strongest association. Tissue Antigens. 1994;43:18–27. [CrossRef] [PubMed]
Schipper RF, Schreuder GM, D’Amaro J, Oudshoorn M. HLA gene and haplotype frequencies in Dutch blood donors. Tissue Antigens. 1996;48:562–574. [CrossRef] [PubMed]
Godfrey WA, Sabates RS, Cross DE. Association of presumed ocular histoplasmosis with HLA-B7. Am J Ophthalmol. 1978;85:854–858. [CrossRef] [PubMed]
Kobayashi H, Kokubo T, Takahashi M, et al. Tyrosinase epitope recognized by an HLA-DR-restricted T-cell line from a Vogt-Koyanagi-Harada disease patient. Immunogenetics. 1998;47:398–403. [CrossRef] [PubMed]
Zipp F, Windermouth C, Pankow H, et al. Multiple sclerosis associated amino acids of polymorphic regions relevant for the HLA antigen binding are confined to HLA-DR2. Hum Immunol. 2000;61:1021–1030. [CrossRef] [PubMed]
Ota M, Mizuki N, Katsuyama Y, et al. The critical region for Behcet disease in the human major histocompatibility complex is reduced to a 46-kb segment centromeric of HLA-B, by association analysis using refined microsatellite mapping. Am J Hum Genet. 1999;64:1406–1414. [CrossRef] [PubMed]

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.