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Steven G E Marsh

Publications and source records attributed to Steven G E Marsh.

At least 19 recordsLinked to original sources
PubMed2026

HLA Diversity of Over 500,000 Individuals on the DATRI Register Across 18 Regions in India.

Registries of unrelated stem cell donors can use HLA haplotype frequencies to aid in registry management. DATRI is India's largest registry with over 550,000 donors, with donors in 35 of India's 36 states and union territories. A geographical based analysis on HLA haplotype frequencies has not previously been carried out with an Indian dataset of this size. To balance granularity and accuracy in estimating 5-locus haplotype frequencies for HLA-A, -C, -B, -DRB1 and -DQB1, we grouped donors into 18 regions with a minimum population size of 2000 donors. We identified the most frequent haplotype as A*33:03-ARD~C*07:01-ARD~B*44:03-ARD~DRB1*07:01-ARD~DQB1*02:01-ARD in Odisha (6.09%), which was also the most frequent haplotype in nine other regions. Assigning the most likely diplotypes to donors, there were a total of 57,959 haplotypes and just 202 (0.3%) of those were present in all 18 regions. HLA-B had the greatest number of alleles across the whole dataset (559) and HLA-DQB1 the least (167). However, HLA-C displayed the most inter-region diversity with only 6.7% of HLA-C alleles present in all regions (average 9.5%). We clustered the regions, using Nei's standard genetic distance, and these correlated with geography; however, three regions (North India, Kerala, and the Gujarat area) did not fit into any cluster. These regions each had one or more distinctive haplotypes that were very frequent (≥ 0.5%) in that region alone. Additionally, the Gujarat area had the lowest diversity metrics. These data can be used to inform the management of registries and contribute to our understanding of HLA diversity globally.

Humans↗
PubMed2006

ISAG/IUIS-VIC Comparative MHC Nomenclature Committee report, 2005.

Nomenclature for Major Histocompatibility Complex (MHC) genes and alleles in species other than humans and mice has historically been overseen either informally by groups generating sequences, or by formal nomenclature committees set up by the International Society for Animal Genetics (ISAG). The suggestion for a Comparative MHC Nomenclature Committee was made at the ISAG meeting held in Göttingen, Germany (2002), and the committee met for the first time at the Institute for Animal Health, Compton, UK in January 2003. To publicize its activity and extend its scope, the committee organized a workshop at the International Veterinary Immunology Symposium (IVIS) in Quebec (2004) where it was decided to affiliate with the Veterinary Immunology Committee (VIC) of the International Union of Immunological Societies (IUIS). The goals of the committee are to establish a common framework and guidelines for MHC nomenclature in any species; to demonstrate this in the form of a database that will ensure that in the future, researchers can easily access a source of validated MHC sequences for any species; to facilitate discussion on this area between existing groups and nomenclature committees. A further meeting of the committee was held in September 2005 in Glasgow, UK. This was attended by most of the existing committee members with some additional invited participants (Table 1). The aims of this meeting were to facilitate the inclusion of new species onto the database, to discuss extension, improvement and funding of the database, and to address a number of nomenclature issues raised at the previous workshop.

Advisory Committees↗
PubMed2006

The IMGT/HLA and IPD databases.

The IMGT/HLA database (www.ebi.ac.uk/imgt/hla) has provided a centralized repository for the sequences of the alleles named by the WHO Nomenclature Committee for Factors of the HLA System since 1998. Since its initial release, the database has rapidly grown in size and is recognized as the primary source of information for the study of sequences of the human major histocompatibility complex. The Immuno Polymorphism Database (IPD; www.ebi.ac.uk/ipd) is a set of specialist databases related to the study of polymorphic genes in the immune system. The IPD currently consists of four databases: IPD-KIR contains the allelic sequences of killer-cell immunoglobulin-like receptors; IPD-MHC is a database of sequences of the major histocompatibility complex of different species; IPD-HPA contains alloantigens expressed only on platelets (human platelet antigens or HPA); and IPD-ESTDAB provides access to the European Searchable Tumour Cell-Line Database, a cell bank of immunologically characterized melanoma cell lines.

Alleles↗