bluuebunny/crossref_metadata_2025_split huggingface dataset:
COMPARISON OF TCR‐αβ SEQUENCES OF CROSS‐REACTIVE ANTI‐DR ALLOREACTIVE T‐CELL CLONES: IDENTIFICATION OF POSSIBLE CONTACT RESIDUES BASED ON CHARGE COMPLEMENTARITY BETWEEN TCR CHAINS AND DR DETERMINANTS
Authors: Champagne E. , Essaket S. , Huchenq A. , Fabron J. , Coppin H. L. , Sevin J. , Thomsen M. 
Published: April 2007

SUMMARYWe analysed alloreactive T‐cell clones selected for their differential recognition of DR variants differing in the third hypervariable region (hvr) of the DRB1 gene (amino acid positions 67–70–71). This polymorphism leads to two main hvr3 types: a basic form (Leu67‐Gln70‐Arg/Lys71) and an acidic form (Ile67‐Asp70‐Glu71) where residue 70 is probably directly accessible to the TCR on DRβ chains. The TCRs have been sequenced. Three DRw13‐reactive clones use similar Va2 and Vβ13 gene family members but differ mainly by their cross‐reactivity towards acidic or basic DR4 variants and by the sequence of CDR3 on their TCRα and/or β chains. One anti‐DRw13 clone cross‐reacts with most specificities sharing the DRw13 type of hvr3 and reciprocally one anti‐DRBon (DRB1*0103) clone cross‐reacts with DRwl3. These two clones use similar V0 genes and share negative charges in CDR2α at position 56. They also share these negative charges in CDR2α with two other clones reacting specifically with DRBon, the acidic variant of DR1. We hypothesized that the selective recognition of positively or negatively charged residues on the DR(3 chain would necessitate reciprocal charges on the TCR complementarity determining regions (CDRs) responsible for this interaction. This facilitated identification of those residues of the TCR that possibly interact with the hvr3 determinant of HLA‐DR. From these observations the mechanisms allowing the recognition of alloantigens by these T‐cell clones are discussed.
DAMAGE IN B2m GENES AND DNA METHYLATION OF H‐2 GENES ARE INVOLVED IN LOSS OF EXPRESSION OF CLASS I MHC PRODUCTS ON THE MEMBRANE OF LR.4, A CELL LINE DERIVATIVE OF THE T‐CELL LYMPHOMA L5178Y
Authors: Nava G. , Ocadiz R. , Ortega V. , Alfaro G. 
Published: April 2007

SUMMARYWe have isolated an H‐2 deficient cell line (LR.4) from the T‐cell lymphoma L5178Y which grew without restrictions in the peritoneal cavity of different inbred strains of mice. The use of polyclonal anti‐H‐2 antiserum and complement indicated that LR.4 cells did not express class I determinants on the cell membrane. Southern blots of genomic DNA of LR.4 cells showed that B2m genes were severely damaged and that class I H‐2 genes were extensively methylated. Consequently, LR.4 cells failed to transcribe mRNAs for both B2m and class I H‐2 genes. On the other hand, specific immunity to LR.4 was demonstrated in C57BL/6J mice since, in subsequent challenges with either LR.4 or EL4.4, LR.4 did not grow, whereas EL4.4 grew and killed the mice. In C57BL/6J mice, rejection of LR.4 was accompanied by the production of cytotoxic antibodies. The immune response induced in C57BL/6J mice was determined by non‐H‐2 antigenic determinants in LR.4 cells.
FINE ANALYSIS OF RECOGNITION SITES OF MONOCLONAL ANTIBODIES, 1B7 AND 1E4, USING L CELL TRANSFECTANTS OF RECOMBINANT MOUSE MHC CLASS II GENES
Authors: Itoh Y. , Ogasawara K. , Onoé K. 
Published: April 2007

SUMMARYRecognition sites of two monoclonal antibodies (mAbs), 1B7 and 1E4, specific for murine MHC class II were determined, using eleven L cell transfectants which express recombinant class II (I‐A) molecules. 1B7 positive cells possessed a haplotype k in the α‐helix of the β‐chain, whereas 1E4 positive cells had haplotype b at the α‐helix of the β‐chain. The α‐helix of the β‐chains is regarded as an important site for antigen binding. Thus, the 1B7 and 1E4 mAbs may be useful for analysis of functional sites on class II molecules involved in antigen recognition.
HLA CLASS II NUCLEOTIDE SEQUENCES, 1992
Authors: Marsh S. G. E. , Bodmer J. G. 
Published: April 2007

SUMMARYThe HLA Class II sequences included in this compilation are taken from publications listed in the papers: Nomenclature for factors of the HLA system, 1991 (Bodmer et al., 1992), Nomenclature for factors of the HLA system, 1990 (Bodmer et al., 1991) and Nomenclature for factors of the HLA system, 1989 (Bodmer et al., 1990). Where discrepancies have arisen between reported sequences, the original authors have been contacted where possible, and necessary amendments to published sequences have been incorporated into this alignment. Future sequencing may identify errors in this list and we would welcome any evidence that helps to maintain the accuracy of this compilation. In the sequence alignments, identity between residues is indicated by a hyphen (‐). An unavailable sequence is indicated by an asterisk (*). Gaps in the sequence are inserted to maintain the alignment between different alleles showing variation in amino acid number.
QUANTITATION OF HLA CLASS II ANTIGENS ON B‐CELL LINES
Authors: BUX J. , SPENGEL U. , MUELLER‐ECKHARDT G. 
Published: April 2007

SUMMARYBy quantitation of elutable immunoglobulin G in a recently described elisa, the number of HLA class I and II molecules on B‐cell lines was determined using monomorphic monoclonal antibodies. An average number of 183 000 binding sites per cell for HLA class I‐, 99000 for HLA‐DR‐, 63000 for DQ‐ and 42000 for DP‐specific monoclonal antibodies were determined. The small amount of HLA class II molecules can in part explain the difficulties observed in HLA class II typing or in detection of class II antibodies using the lymphocytotoxicity text.
HLA CLASS II POLYMORPHISM AND IDDM SUSCEPTIBILITY IN THE GREEK POPULATION
Authors: Khalil I. , Spyropoulou M. , Mallet C. , Loste M. N. , Douay C. , Laperriere J. , Bartzokas C. , Lepage V. , Charron D. , Stavropoulos C. 
Published: April 2007

SUMMARYThe frequencies of HLA‐DQA1, DQB1 and DRB1 alleles were compared between 50 Insulin‐Dependent Diabetes Melitus (IDDM) patients and 49 healthy controls in the Greek population. Statistically significant difference in the frequencies of HLA‐DQA1*0501‐DQB1*0201 (P = 10‐4), DQA1*0301‐DQB1*0201 (P= 0.01) and DQA P0301‐DQB 1*0302 (P= 0.001) were observed. The DRB1*0405‐DQA1*0301‐DQB 1*0201 was the only DR, DQ combination significantly associated with the disease. The unexpected increase of DRB1*0405 observed in the Greek IDDM may suggest as reported in Chinese and Japanese IDDM a contribution of DRβ and DQα in susceptibility. Moreover, in contrast to the Asians, in the Greek, the DRβ, DQα are found with the usual DQβ 57‐ve.
T‐CELL RECEPTOR α, δ, AND γ CHAIN GENES IN INSULIN‐DEPENDENT DIABETES MELLITUS
Authors: Martianez‐Naves E. , Penta M. , Loapez‐Larrea C. 
Published: April 2007

SUMMARYWe have studied the genotypic, haplotypic, and allelic distribution of germline Restriction Fragment Length Polymorphism (RFLP) of T‐cell receptor (Tcr) α, γ, and δ loci in 75 insulin‐dependent diabetes mellitus (IDDM) patients and 84 healthy blood donors as control population. The restriction endonuclease PvuII produces three allelic fragments of Tcr C‐γ (TcrCG) gene segment of 16,13, and 11.3 Kb respectively. Our observations revealed that PvuII/TcrCG RFLP allelic distributions were not significantly different in the IDDM and the control group. However, 85% of IDDM patients carried HLA DR3 and/or DR4 haplotypes, and when comparing these patients with a second group of HLA DR3+ and/or DR4+ healthy individuals, the 11Kb/PvuII fragment of TcrCG gene was found to be associated with IDDM patients (χ= 11.4, P= 0.003). 54.9% of IDDM patients carried at least one 11.3 Kb allele vs. 21% in controls (χ= 10.77, P = 0.004). No significant association was found between RFLP in Tcr, Cα, Cδ, Vγ9 loci and IDDM.
INVASIVE SQUAMOUS CELL CARCINOMA OF THE CERVIX: IS HLA‐DQ A DISEASE MARKER IN JEWISH PATIENTS?
Authors: Amar A. , Battat S. , Anteby S.O. , Brautbar C. , Reubinoff B.E. 
Published: April 2007

SUMMARYHLA class I and class II were investigated in 30 Israeli patients with invasive squamous cell carcinoma of the cervix and compared to healthy controls. None of the studied serological specificities were found to be associated with the disease. Genomic DNA from the patients was amplified by PCR, dot‐blotted and hybridized with sequence specific oligonucleotide probes defining the known DQA1 and DQB1 allelic variants. Fifteen out of the 30 patients tested (50%) were found to carry the DQA1*0501 allelic variant, which is common in the local healthy population (67%). DQB 1*0302 was found in eight out of 30 patients (27%) while this allele was present in 17% of the healthy population, a difference which is not statistically significant. Our data indicate that there is no apparent association between invasive squamous cell carcinoma of the cervix and the HLA antigens and alleles studied including the alleles of the DQ A and DQB loci in the Israeli population. Our findings indicate that MHC genes could not be useful in the diagnosis of squamous cell carcinoma of the cervix.
ABSENCE OF STRONG HLA‐DR/DQ‐DP LINKAGE DISEQUILIBRIUM IN THE BRITISH AND FRENCH CANADIAN CAUCASOID POPULATIONS
Authors: Howell W.M. , Evans P.R. , Devereux S.A. , Sage D.A. , Smith J.L. , Haegert D.G. 
Published: April 2007

SUMMARYHLA‐DR/DQ‐DP linkage disequilibrium was investigated in healthy, unrelated British (n= 150) and French Canadian (n= 67) caucasoid subjects. HLA‐DR and DQ typing was performed by Taq I DNA‐RFLP analysis, while DPB1 typing was performed by PCR‐SSOP. χ2 and Fisher's exact tests were performed for all 2‐locus biallelic comparisons and coefficients of linkage disequilibrium determined.In the British population, only one example of linkage disequilibrium, significant at P= 0.05 (after correction for the number of comparisons made) was seen (DPB1*0101‐DRB1*0301[171]). Additional associations, significant at P = 0.05 before correction for the number of comparisons were also seen, including DPB1*0401‐DRB1*15, DPB1*1101‐DRB1*0701(71), DPB1*1701‐DRB1*0701/ 2(72), DPB1*0101‐DQA1*0501, DPB1*0401‐DQA1*0102, DPB1*0501‐DQA1*0102, DPB1*0101‐DQB1*0201, DPB1*0401‐DQB1*0602/0603 and DPB1*1101‐DQB1*0201. With one exception (DPB1*1101‐DQB1*0201), none of these associations was seen in the French Canadian group.These results indicate that although more frequent than thought hitherto, HLA class II linkage disequilibrium involving DPB1 alleles is generally weak, and can differ even between different caucasoid populations. This may have implications for HLA and disease studies.
GENOMIC MHC HAPLOTYPING OF MUTANT CELL LINES USING A NOVEL MARKER
Authors: Degli‐Esposti M.A. , Williamson J.F. , Tay G.K. , Salmon B. , Joseph G.A. , Morley A.A. , Dawkins R.L. 
Published: April 2007

SUMMARYThe aim of this study was to characterize MHC mutant cell lines by studying haplospecific markers within the MHC and specifically in the 250 kilobase (kb) region between the HLA B and TNF loci. This region has been difficult to define because of the lack of appropriate markers. Spontaneous MHC mutants were isolated after immunoselection with an anti‐HLA A2 monoclonal antibody and complement. Ten mutants were characterized using serological or allelic and genomic DNA markers within the HLA A to HLA DQ region of the MHC. Most mutants lost at least the 3 megabases of DNA from HLA A to HLA DQ viz the whole haplotype carrying HLA A2. Variants which have lost either HLA A alone or HLA A and HLA B were also found. The results show that it is possible to map the extent of the deletion between HLA B and TNF. Haplospecific scanning patterns for the CL region appear particularly useful.
ROLE OF A GENETIC REGION ON CHROMOSOME 4 IN THE REGULATION OF NATURAL KILLER CELL ACTIVITY IN MICE
Authors: Dubey D.P. , Mirza N.M. , Zaharian B.I. , Yunis E.J. 
Published: April 2007

SUMMARYNatural killer cell (NK) activity is regulated by both the H‐2 and non‐H‐2 genes. Using bilineal congenic HW26C and HW13 mice which differ from the background strain C57BL/6By (B6) in a region of chromosome 4, we investigated the role played by a gene/genes in a segment of chromosome 4 of BALB/cBy on NK cell activity. Percoll separated low density spleen cells from young HW26C and HW13 mice showed a 3.5 fold higher NK activity than the B6. We also observed that the increase in NK activity of HW26C was not due to an increase in the number of NK cells. Using five other bilineal congenics containing different regions of chromosome 4 of BALB/cBy, we observed that the putative gene(s) regulating NK activity may be located between b and IFN‐α/β genes of chromosome 4. The level of NK activity of (B6xHW26C)F1 ranked between the HW26C and B6 suggesting that the gene product described is inherited in an incompletely dominant fashion.
PERIPHERAL TOLERANCE TO ALLOANTIGEN: STRATEGIES FOR THE FUTURE
Authors: Wood K. J. 
Published: April 2007

SUMMARYThe mature, adult immune system is specifically designed to eliminate any foreign material that may enter the body, but not to respond to the body's own tissues and molecules. Indeed, during development, the potential of the immune system to respond to self antigens is removed, by eliminating or effectively silencing any autoreactive cells. These features are well adapted under normal circumstances, as they result in the efficient elimination of potentially harmful agents thereby protecting the body from infection and malignancy. However, in the context of transplantation, this ‘normal’ response is diametrically opposed to the desired clinical outcome, which is clearly the long term function and survival of the transplanted tissue. To prevent graft rejection the immune system of the transplant recipient has to be manipulated to ensure that it is incapacitated. Immunosuppressive drugs can be used for this purpose and are undoubtedly effective; indeed they have had a dramatic impact on success rates in clinical organ transplantation. However, as the mechanism of action of these chemical immunosuppressants is immunologically non‐specific, any immune response the recipient may need to make after transplantation, as well as the rejection response, is suppressed. In addition, to maintain graft survival the drugs have to be taken indefinitely after transplantation and therefore their use is not only associated with immunological complications such as increased risks of infection and malignancy, but also numerous non‐immunological side‐effects. One way to overcome these problems would be to develop strategies for specific immunosuppression, such that only leukocytes capable of responding to the foreign histocompatibility or alloantigens expressed by the transplanted tissue would be affected. The ability to manipulate or reprogramme the adult immune system in such a way as to induce specific immunological unresponsiveness or tolerance to the alloantigens of the organ donor would offer many advantages over conventional immunosuppressive therapy. Only leukocytes reactive with donor alloantigens would be affected, thus allowing transplant recipients to respond effectively to other immunological stimuli, such as virus infections.
DETERMINATION OF DRB ALLELES USING PCR AMPLIFICATION AND ALLELE‐SPECIFIC PRIMERS
Authors: Lepage V. , Schaeffer V. , Mallet C. , Ivanova R. , & I. Khalil , Charron D. 
Published: April 2007

SUMMARYHLA class‐II allelic diversity is commonly defined using polymerase chain reaction (PCR) in combination with sequence‐specific oligotyping (PCR‐SSO) or the combination of PCR and restriction fragment length polymorphism methods (PCR‐RFLP). Nevertheless, the identification of the DRB polymorphism by PCR‐SSO is a time‐consuming procedure and the PCR‐RFLP is cumbersome. A rapid technique which allows a precise and extensive HLA‐DRB typing is required, particularly in order to study the role of class‐II matching in organ transplantation. A DRB typing method based on the detection and length of PCR products amplified using combination of allele specific primers has been developed. Thirty‐four DRB alleles (29 DRB1, 4DRB3, 1DRB4) can be detected using 29 primers distributed into 19 amplification mixtures.
DRB, DQA, DQB AND DPB NUCLEOTIDE SEQUENCES OF SANGUINUS OEDIPUS B95‐8
Authors: Bidwell J. L. , Lu P. , Wang Y. , Zhou. K. , Clay T. M. , Bontrop R. E. 
Published: April 2007

SUMMARYWe present eight new nucleotide sequences derived from the second exons of class II genes within the major histocompatibility complex of Sanguinus oedipus (cotton‐top tamarin). These comprise two DRB alleles (Saoe‐DRB3*0504, ‐DRB*w1203), two DQA1 alleles (Saoe‐DQA1*2501, ‐DQA1*2502), two DQB1 alleles (Saoe‐DQB1*2201, ‐DQB1*2301), one DQB2 allele (Saoe‐DQB2*0101) and one DPB1 allele (Saoe‐DPB1*0101).
FREQUENCY OF HLA‐DPB1 ALLELES IN A SPANISH POPULATION: THEIR CONTRIBUTION TO RHEUMATOID ARTHRITIS SUSCEPTIBILITY
Authors: Yélamos J. , Garcéa‐Lozano J.R. , Moreno I. , Romero M. , Garcéa A. , Sánchez B. 
Published: April 2007

SUMMARYHLA‐DPB1 allele frequencies in 181 unrelated control individuals and 70 rheumatoid factor‐positive RA patients from Seville (Spain) were determined using oligonucleotide typing methods. All frequencies shown concern the percentage of individuals positive for a certain allele. HLA‐DPB1*0401 was the most common DPB1 allele in the healthy individuals, possessed by 65.7% of them. In addition to HLA‐DPB1 *0401, only the following alleles were found in normal subjects at frequencies greater than 10%: DPB1*0101 (15.5%), DPB1*0201 (12.2%), DPB1*0301 (16.6), and DPB1*0402 (29.3%). When HLA‐DPB1 allelic frequencies were compared between seropositive RA patients and controls, a negative association for DPB1*0301 and DPB1*0401 was found in RA patients, although it failed to reach statistical significance after correction for the number of comparisons made. The other DPB1 alleles exhibited almost identical frequencies in both groups. However, when only DR4+ patients and controls were considered, the decrease in the frequency of the DPB1*0301 and DPB1*0401 alleles lacked statistical significance. On the other hand, when DR4‐ RA patients and controls were compared, the frequency of DPB1*0301 was found decreased significantly again, even more than in the whole group of patients.
DISTRIBUTION OF HLA‐A*28 ALLELES IN A SPANISH POPULATION
Authors: Yélamos J. , González M. F. , Garcéa‐Lozano J. R. , Sánchez B. 
Published: April 2007

SUMMARYDNA oligotyping was used to determine HLA‐A28 subtypes in 25 unrelated Caucasian individuals living in or around Seville, Spain. Results showed that HLA‐A*6802 was the most frequent allele, found in 14 individuals (53.8%), followed by HLA‐68.3, which was present in eight subjects (30.8%), and both combined represented 84.6% of A28+ individuals in the area. The HLA‐A*6801 allele was found in three individuals (11.5%), whereas HLA‐A*6901 was present in one subject only (3.8%). Results indicate that the distribution of HLA‐A28 alleles can vary among different Caucasoid populations. In this way, the high frequency obtained for A*6802 supports previous studies suggesting that the HLA‐A*6802 allele was prevalent in people of the Mediterranean basin, in contrast to A*6801, prevalent in northern European populations.
A WILD‐TYPE μs C‐TERMINAL GENE IS EXPRESSED IN BLOOM'S SYNDROME CELLS
Authors: Ozawa T. , Kondo N. , Kato Y. , Motoyoshi F. , Suzuki Y. , Shimozawa N. , & K. Kasahara , Orii T. 
Published: April 2007

SUMMARYSelective IgM deficiency is found commonly in patients with Bloom's syndrome (BS). Serum IgM concentrations were low though serum IgG and IgA concentrations were normal in both patients with BS included in the study. In a previous study the authors showed that selective IgM deficiency in BS is due to an abnormality in the maturation of surface IgM‐bearing cells into IgM‐secreting cells and a failure of secreted μ (μ s) mRNA synthesis. The membrane‐bound μ (μ m) and μ s mRNA are produced from transcripts of a single immunoglobulin μ gene by alternative RNA processing pathways. The control of μ s mRN A synthesis depends on the addition of poly(A) to μ s C‐terminal segment. The study described here demonstrated that there was no mutation or deletion in the sequence including μ s C‐terminal coding sequence, the RNA splice site (GG/TAAAC) at the 5’ end of μ s C‐terminal segment, and the AATAAA poly(A) signal sequence, and second GT‐rich element immediately down‐stream of the cleavage site in both patients.
HLA‐DPB1 DNA POLYMORPHISM IN THE SWISS POPULATION: LINKAGE DISEQUILIBRIUM WITH OTHER HLA LOCI AND POPULATION GENETIC AFFINITIES
Authors: Grundschober C. , Sanchez‐Mazas A. , Excoffier L. , Langaney A. , Jeannet M. , Tiercy J.‐M. 
Published: April 2007

SUMMARYAllelic diversity at the HLA‐DPB1 locus was determined by PCR‐oligotyping in a sample of 125 healthy Swiss individuals. A total of 17 alleles were detected among which four main alleles (DPB 1*0401, *0201, *0301, *0402) reached a cumulative frequency of 74.8%. HLA‐A and ‐B (by serology) and HLA‐DRB1 (by oligotyping) allelic polymorphisms were analysed also. HLA‐B and HLA‐DRB1 loci were highly polymorphic with 25 and 28 alleles respectively and similar heterozygosity levels of 0.93 and 0.92. These two loci were found to be more polymorphic than expected under neutrality, while lower heterozygosity levels were found for HLA‐A (0.87) and DPB1 (0.81) loci. This paper presents also a global comparison of DPB1 allelic frequencies among 15 populations from four continents. As opposed to the DRB1 locus, overall DPB1 is shown to have a lower level of polymorphism and may be considered as neutral in all tested populations. DPB 1 genetic diversity is correlated significantly with geography also, as found previously for DRB1. Two‐ and four‐locus haplotype frequencies were determined and the significance of their linkage disequilibrium tested by an original non‐parametric method. A significant positive linkage disequilibrium was found for 11 A‐B, 16 B‐DRB1, 7 DRB1‐DPB1 and 3 A‐B‐DRB1‐DPB1 haplotypes. The overall linkage disequilibrium between DRB1 and DPB1 was much lower than expected from the physical distance and lower than for A‐B and B‐DRB1 pairs. The implications of these results for bone marrow transplantation and for the evolution of HLA loci are discussed.
COMPLEXITY OF THE BOVINE MHC CLASS‐II SPECIFICITY DW3 AS DEFINED BY ALLOANTISERA
Authors: Nilsson Ph. R. , Van't Klooster J. W. , Van Der Poel J. Y. , Davis W. C. , Schreuder G. M. T. 
Published: April 2007

SUMMARYAlloantisera related to the bovine major histocompatibility complex (MHC) class‐II specificity Dw3 were investigated by cross‐absorption experiments and by application of the monoclonal antibody‐specific immobilization of lymphocyte antigen assay (MAILA). The absorption study revealed antibodies specific for an antigenic determinant shared by all Ds03 (Dw3)‐positive animals, and several other antibody populations recognizing the locally defined specificites Ds10, Ds11 and Ds15, that are closely associated with Ds03. The results of the MAILA‐assay indicate that the Ds03 specificity is probably encoded by DQ, whereas specificities Ds10 and Ds11 are more closely associated with DR molecules. The data presented here provide the first evidence that bovine DR and DQ specificities can be identified separately by serological methods using alloimmune antisera.
GENOMIC STRUCTURE AND ORGANIZATION OF A Q‐LIKE GENE IN THE GRC‐GIC REGION OF THE RAT
Authors: Rushton J. J. , Misra D. N. , Kunz H. W. , Cortese Hassett A. L. , Gill T. J. 
Published: April 2007

SUMMARYIn the rat homologue of the mouse Q/TL region, grc‐G/C, a TL‐like gene (RT1.N) has been identified recently. This paper reports on a Q‐like gene, designated RT1.0, that maps in the same region. It contains a 5’ untranslated region (UT), signal peptide, α3 domain, transmembrane region, cytoplasmic domain (three exons) and 3′ UT region. Comparison with mouse class‐I genes shows that the greatest similarity is to the H‐2Q, K, D and L genes; it is very different from the TL genes of the mouse and rat. A sequence that includes many CT repeats occurs in the 3′UT region of RT1.0 and in three to five other class I‐hybridizing fragments. Thus, the MHC‐linked region of the rat contains both Q‐like and TL‐like class‐I genes.