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C K Hurley

Publications and source records attributed to C K Hurley.

At least 55 records · Page 3Linked to original sources
PubMed2000

Relative frequencies of DRB1*11 alleles and their DRB3 associations in five major population groups in a United States bone marrow registry.

One hundred sixty-one individuals from each of five US population groups, Caucasians (CAU), African Americans (AFA), Asians/Pacific Islanders (API), Hispanics (HIS), and Native Americans (NAT), were randomly selected from a volunteer bone marrow registry database consisting of 14,452 HLA-DRB1*11 positive individuals. This sampling provided at least an 80% probability of detecting a rare allele that occurred at 1% in the DRB1*11 positive population. Samples were typed for DRB1*11 alleles by polymerase chain reaction-sequence specific oligonucleotide probe typing (PCR-SSOP). A total of 10 DRB1*11 alleles out of 27 possible alleles were detected. The distribution and diversity of DRB1*11 alleles varied among populations although DRB1*1101 was the predominant DRB1*11 allele in all populations. Caucasians were the least diversified; only four common alleles (DRB1*1101-*1104) were observed. As well as the four common alleles, other groups also carried one or two other less frequent alleles including DRB1*1105 (API), *1106 (API), *1110 (AFA), *1114 (HIS), *1115 (NAT), and *1117 (AFA). A subset (418) of these individuals were also typed for DRB3 alleles. Most (97.6%) showed a strong association of DRB1*11 with DRB3*0202.

Black or African American↗
PubMed2000

The relative frequencies of HLA-DRB1*01 alleles in the major US populations.

The frequencies of alleles in the HLA-DRB1*01 family were determined in each of five US populations from a database of 82,979 individuals. Individuals typed as DR1 (or DRB1*01) comprised between 7.6%-21.3% of the individuals in each population group. Fifty-nine DR1 individuals were randomly selected from each group and subjected to high-resolution DNA typing by polymerase chain reaction using sequence-specific oligonucleotide probes. DRB1*0101 was the most common allele in the Caucasian, Asian/Pacific Islander, and Native American groups while the DRB1*0102 allele was found in the majority of African Americans and Hispanics. DRB1*0103 was present at a similar frequency in all populations. DRB1*0104, DRB1*0105, and DRB1*0106 alleles were not observed.

Alleles↗
PubMed2000

Large-scale DNA-based typing of HLA-A and HLA-B at low resolution is highly accurate specific and reliable.

DNA-based typing of HLA class I alleles of the HLA-A and HLA-B loci using sequence-specific oligonucleotide primers and/or probes has been used for the large-scale typing of individuals for the National Marrow Donor Program unrelated donor registry. Typing was performed by 16 laboratories at a low level of resolution (e.g. A*01, B*07). The results of blinded quality control analysis for the first 12 months of the project show the typing to be highly accurate, specific and reliable. The total error rate based on 11,545 HLA-A and 11,428 HLA-B assignments was 1.1% for HLA-A and 1.9% for HLA-B. This level of accuracy is particularly remarkable because the quality control samples could not be distinguished from 64,180 donor samples tested at the same time by the laboratories.

Bone Marrow Transplantation↗
PubMed2000

Seventeen more novel HLA-A locus alleles.

This paper describes seventeen novel HLA-A locus alleles: A*0106, *0235, *0236, *0237, *1105, *2302, *2303, *24032, *2422, *2424, *2503, *2613, *3007, *3203, *3204, *6809 and *6810. All alleles were identified due to unexpected probe reaction patterns during routine SSOP typing. Exons 2 and 3 of these alleles were subsequently characterized by DNA sequencing. The alleles represent a shuffling of sequence motifs, likely by interallelic conversion, expanding the diversity of the HLA system.

Alleles↗
PubMed2000

The relationship between HLA-B45 and B* 5002 in the five major U.S. population groups.

The antigen encoded by B*5002 differs in sequence from that encoded by B*5001 only at amino acid residue 167 (consensus tryptophan vs. serine) which results in B45 serologic reactivity. To search for B*5002, the frequencies of alleles encoding the serologically defined B45 antigen were determined by sequence-based typing in 5 major U.S. populations: Caucasians, African Americans, Asians/Pacific Islanders, Hispanics, and Native Americans. The percent of serologically defined B45-positive individuals in the 5 populations ranged from 0.7-9.0%. Thirty-two B45-positive individuals were randomly chosen, when available, for sequence-based typing from each ethnic group from a database of 82,979 consecutively typed unrelated individuals. The B*5002 allele was most prevalent in Hispanic (22%) and Caucasian (9%) individuals, while conspicuously absent in African Americans. In addition, a new allele associated with the B45 antigenic specificity, B*4502, has been identified from an African American individual of Middle Eastern descent. In light of the continuing need to reconcile differences between relationships determined by the sequence homologies among alleles and relationships based on the serologic determinants carried by allelic products when determining the level of HLA match for hematopoietic stem cell transplantation, it is suggested that B*5002 be recognized individually from other B*50 alleles when reporting HLA-B typings for clinical purposes.

Alleles↗
PubMed2000

DRB3 alleles with variations in the annealing sites of commonly used amplification primers.

New HLA alleles are often identified initially from observing uncommon patterns found in low-resolution typing performed via polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP). Recently, the HLA-DR oligotyping analysis of two Caucasian, one Caucasian/American Indian and two African American individuals resulted in the identification of three novel DRB3 alleles. Using DRB-specific primer sets commonly employed in amplification-based typing, all four individuals were originally characterized as DRB3 negative. Direct sequencing identified DRB3*0104 (variation at codon 8, TCG instead of TTG), and DRB3*0101202 (variation at intron (-13), G instead of C). One individual appeared to carry a DR52-associated DRB1 allele without an associated DRB3 allele. Lack of conservation at the junction of intron 1 and exon 2 of the DRB3 gene suggests that commonly used DRB-specific primer sets may need to be modified.

Alleles↗
PubMed2000

Going back to the roots: effective utilisation of HLA typing information for bone marrow registries requires full knowledge of the DNA sequences of the oligonucleotide reagents used in the testing.

Information obtained by DNA-based HLA typing assays is more detailed and of higher quality than that obtained by conventional serological techniques. Nevertheless, it is common for data acquired in this way to be presented in the more familiar serological format. In many cases this representation can lead to significant loss of information, which may only become apparent at a later time, with the discovery of novel allele sequences. DNA-based typing methods, such as sequence-specific oligonucleotide probing (SSOP) or sequence-specific priming (SSP) generate fragmentary sequence data which is information rich. An alternative to assigning allele names to these fragments is to simply store the sequence data itself without interpretation. Bone marrow donor repositories can then be searched directly with sequence information, which though complex is more complete, rather than searching by derivative allele names.

Base Sequence↗
PubMed2000

Diversity is demonstrated in class I HLA-A and HLA-B alleles in Cameroon, Africa: description of HLA-A*03012, *2612, *3006 and HLA-B*1403, *4016, *4703.

To examine the genetic diversity in west Africa, class I HLA-A and HLA-B alleles of 92 unrelated individuals from two areas in the Cameroon, the capital Yaoundé and the village of Etoa, were identified by direct automated DNA sequencing of exons 2 and 3 of the HLA-B locus alleles and sequence-specific oligonucleotide probe (SSOP) and/or sequencing of the HLA-A locus alleles. HLA-A*2301 (18.7%), A*2902 (10.4%), B*5301 (10.9%), and B*5802 (10.9%) were the most frequently detected alleles, present in at least 10% of the population. A total of 30 HLA-A locus and 33 HLA-B locus alleles, including six novel alleles, were detected. The novel alleles were HLA-A*03012, A*2612, A*3006 and HLA-B*1403, B*4016, and B*4703. HLA-B*4703 contains a novel amino acid sequence that is a combination of the first 5 amino acids of the Bw6 epitope and the last 2 residues of the Bw4 epitope. The addition of 6 alleles to the ever-expanding number of known class I HLA alleles supports our hypothesis that extensive genetic diversity, including previously undescribed alleles, would be observed in this African population. In the Yaoundé population, the allele frequency distribution at the HLA-A locus is consistent with distributions indicative of balancing selection. Extensive HLA-A-B haplotypes were observed in this population suggesting that only a fraction of the Cameroon HLA-A-B haplotype diversity has been observed.

Alleles↗
PubMed2000

The extent of HLA class II allele level disparity in unrelated bone marrow transplantation: analysis of 1259 National Marrow Donor Program donor-recipient pairs.

A comprehensive analysis of the HLA-D region loci, DRB1, DRB3, DRB5, DQA1, DQB1, DPA1 and DPB1, was performed to determine allelic diversity and underlying HLA disparity in 1259 bone marrow recipients and their unrelated donors transplanted through the National Marrow Donor Program. Although 43.0% of DRB1 alleles known to exist at the beginning of the study were found in this predominantly Caucasian transplant population, a few alleles predominated at each locus. In recipients, 67.1% of DRB1 alleles identified were one or two of six common DRB1 alleles. Only 118 (9.4%) donor-recipient pairs were matched for all alleles of DRB1, DQA1, DQB1, DPA1 and DPB1. While 79.4% of the pairs were matched for DRB1, only 13.2% were matched for DPB1 alleles. Almost 66% of pairs differed by more than one allele mismatch and 59.0% differed at more than one HLA-D locus. DQB1 was matched in 85.9% of DRB1-matched pairs. In contrast, only 13.9% of the pairs matched for DRB1, DQA1 and DQB1 were also matched for DPA1 and DPB1. This database, highlighting the underlying HLA disparity within the pairs, forms the foundation of an ongoing study to establish the relationship between HLA matching and successful outcome in unrelated allogeneic stem cell transplant.

Alleles↗
PubMed2000

Maintaining updated DNA-based HLA assignments in the National Marrow Donor Program Bone Marrow Registry.

The National Marrow Donor Program (NMDP) has instituted an approach to address the impact of new alleles on the DNA-based HLA assignments obtained during volunteer donor typing. This approach was applied to the DRB typing results from 371,187 donors received from 14 laboratories in 1999. Samples were tested with a standardized set of sequence specific oligonucleotide reagents and the positive and negative hybridization results transmitted electronically to the NMDP. A software program interpreted the primary data into HLA assignments and rejected assignments which did not produce a result at the specified level of resolution. Comparison of the HLA assignments derived by the NMDP software to the assignments made by the laboratories using several local software prograins showed 90.5% of the assignments to be identical. Differences in assignments were explained by varying levels of typing resolution, variation in the inclusion of the second expressed DRB loci, disparity arising when alternative assignments were summarized, and failure to submit correct information. When the primary data collected in 1999 were interpreted into HLA assignments using the set of alleles defined in July 2000, 74% of the HLA-DRB assignments were altered by the description of new alleles, justifying the development of this software.

Base Sequence↗
PubMed1999

HLA-A*28 allele frequencies in the five major U.S. ethnic groups.

The frequency of each A*28 allele was determined by PCR-SSOP typing in 5 major U.S. ethnic populations: Caucasians, African Americans, Asians/Pacific Islanders, Hispanics, and Native Americans. The percent of serologically defined A28-positive individuals in the 5 populations ranged from 2.7-17.9%. Fifty-nine individuals who were previously serologically typed as A28, A68 or A69 were randomly chosen for allele-level typing from each ethnic group from a database of 82,979 consecutively typed unrelated individuals. The most common A*28 allele for Caucasians, Asians/Pacific Islanders, Hispanics, and Native Americans was A*68012, while A*6802 was found in the majority of African Americans. Only four and three A*28 alleles were seen in Caucasians and African Americans, respectively, while five to six A*28 alleles were seen in the other population groups. The A*6804 and A*6806 alleles were not observed in any of the five ethnic groups.

Alleles↗
PubMed1999

A special report: histocompatibility testing guidelines for hematopoietic stem cell transplantation using volunteer donors. Quality Assurance and Donor Registries Working Groups of the World Marrow Donor Association.

The World Marrow Donor Association has formulated guidelines for establishing the extent and quality of histocompatibility testing for unrelated donor registries, umbilical cord blood banks, and transplant centers involved in international exchange of hematopoietic stem cells for allogeneic transplantation. Registry and cord blood bank guidelines suggest that, at a minimum, initial HLA typing should be performed for three HLA loci, HLA-A, -B, and -DR, at low resolution/split antigen level. DNA-based testing methods should be utilized for HLA-DR typing. DNA-based testing for HLA-A and -B should replace serologic testing of new volunteer donors and cord blood units as robust protocols and reagents become available to the laboratories. Transplant center guidelines for typing of patient, family and to confirm the HLA types of potential unrelated donors should include, at the minimum, typing HLA-A, B, and -DR loci using primarily DNA-based testing methods at allele level resolution for DRB1 and low resolution/split antigen level for HLA-A and -B. It is strongly recommended that the typing of a patient and the selected donor be performed using the same set of reagents, methodology, and interpretation criteria with fresh tissue samples to ensure HLA identity. Guidelines for laboratory accreditation, approaches to quality assurance and quality control for HLA testing, and suggestions for the format of the HLA database of donor types are also outlined.

Bone Marrow Transplantation↗
PubMed1999

Relative HLA-DRB1*13 allele frequencies and DRB3 associations of unrelated individuals from five US populations.

The frequencies of 30 HLA-DRB1*13 alleles and 15 DRB3 alleles were determined for the 5 major U.S. ethnic populations: Caucasians, African Americans, Asian/Pacific Islanders, Hispanics, and Native Americans. A random sampling (163) of DRB1*13-positive individuals from each self-described ethnic group was selected out of a pool of 82,979 unrelated individuals, providing at least an 80% probability of detecting a rare allele that occurred at 1%. These 815 samples were subjected to allele-level SSOP typing and/or DNA sequencing which identified 11 different DRB1*13 alleles. DRB1*1301 and DRB1*1302 were the most common alleles seen in the five major ethnic groups while DRB1*1304 was not detected among Caucasians and DRB1*1305 was not detected among African Americans. DRB1*13 allele diversity was surprisingly more limited among African Americans compared to both Caucasians and Asian/Pacific Islanders. To determine the extent of DRB1*13-DRB3 associations, 504 of these samples expressing only one DRB3-associated DRB1 allele were subjected to PCR-SSOP typing and 14 DRB1*13-DRB3 haplotypes were detected. The distribution revealed that African Americans were significantly different from Caucasians, Asian/Pacific Islanders, and Hispanics. Allele frequency studies such as this further support previous findings that the distribution of HLA types can differ significantly among different ethnic populations.

Alleles↗
PubMed1999

The HLA dictionary 1999: a summary of HLA-A, -B, -C, -DRB1/3/4/5, -DQB1 alleles and their association with serologically defined HLA-A, -B, -C, -DR, and -DQ antigens.

This report presents serologic equivalents of 90 HLA-A, 190 HLA-B, and 145 HLA-DRB1 alleles. The equivalents cover over 70% of the presently identified HLA-A, -B, and -DRB1 alleles. The dictionary is an update of the one published in 1997 and now also includes equivalents for HLA-C, DRB3, DRB4, DRB5, and DQB1 alleles. The data summarize information obtained by the WHO HLA Nomenclature Committee, the International Cell Exchange (UCLA), the National Marrow Donor Program (NMDP), and by individual laboratories. In addition, a listing is provided of alleles that are expressed as antigens with serologic reaction patterns that differ from the well-established HLA specificities and that often lack official WHO nomenclature. The provided equivalents will be useful in guiding searches for unrelated donors in which patients and/or potential donors are typed by either serology or DNA-based methods. These equivalents will also serve typing and matching procedures for organ transplant programs where HLA typings from donors and from recipients on waiting lists represent mixtures of serologic and molecular typings. Some guidelines are provided for the use of appropriate WHO HLA nomenclature for serologic typings and for generic and allele specific typings obtained with molecular methods. The tables with HLA equivalents and the questionnaire for submission of serology on poorly identified alleles will also be available at the WMDA web page: www.bmdw.org/wmda.

Alleles↗
PubMed1999

A special report: histocompatibility testing guidelines for hematopoietic stem cell transplantation using volunteer donors.

The World Marrow Donor Association has formulated guidelines for establishing the extent and quality of histocompatibility testing for unrelated donor registries, umbilical cord blood banks, and transplant centers involved in international exchange of hematopoietic stem cells for allogeneic transplantation. Registry and cord blood bank guidelines suggest that, at a minimum, initial HLA typing should be performed for three HLA loci, HLA-A, -B, and -DR, at low resolution/split antigen level. DNA-based testing methods should be utilized for HLA-DR typing. DNA-based testing for HLA-A and -B should replace serologic testing of new volunteer donors and cord blood units as robust protocols and reagents become available to the laboratories. Transplant center guidelines for typing of patient, family and to confirm the HLA types of potential unrelated donors should include, at the minimum, typing HLA-A, B, and -DR loci using primarily DNA-based testing methods at allele level resolution for DRB1 and low resolution/ split antigen level for HLA-A and -B. It is strongly recommended that the typing of a patient and the selected donor be performed using the same set of reagents, methodology, and interpretation criteria with fresh tissue samples to ensure HLA identity. Guidelines for laboratory accreditation, approaches to quality assurance and quality control for HLA testing, and suggestions for the format of the HLA database of donor types are also outlined.

Hematopoietic Stem Cell Transplantation↗
PubMed1999

The relative frequencies of HLA-A*10 alleles in five major United States ethnic populations.

The frequency of each A*10 allele was determined in 5 major United States ethnic populations randomly selected from a pool containing 82,979 unrelated individuals. The phenotype frequency of A10 was 10.5% in Caucasians, 14.0% in African-Americans, 21.1% in Asians/Pacific Islanders, 10.6% in Hispanics, and 9.8% in Native Americans. Fifty-nine individuals who had at least one A10 antigen were randomly chosen from each ethnic group for polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP) typing. Thirteen of sixteen known A10 alleles were identified in this pool. The most common alleles observed were: A*2601 in Caucasians (55%), Hispanics (58%), and Native Americans (45%); A*3402 in African-Americans (34%); and A*3401 in Asians/Pacific Islanders (61%). The African-American and Asian/Pacific Islander populations differ from all other populations in the distribution of A*10 alleles, particularly, A*2601, A*3401, and A*3402.

Black or African American↗