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81.
Jerzy K. Kulski Atsuko Shigenari Takashi Shiina Kazuyoshi Hosomichi Makoto Yawata Hidetoshi Inoko 《Immunogenetics》2009,61(4):257-270
The study of the association of the Human Leukocyte Antigen (HLA) alleles and polymorphic retrotransposons such as Alu, HERV, and LTR at various loci within the Major Histocompatibility Complex allows for a better identification and stratification of disease associations and the origins of HLA haplotypes in different populations. This paper provides sequence and association data on two structurally polymorphic MER9-LTR retrotransposons that are located 54 kb apart and in close proximity to the multiallelic HLA-A gene involved in the regulation of the human immune system. Direct DNA sequencing and analysis of the PCR products identified DNA nucleotide variations between the MER9-LTR sequences at the two loci and their associations with HLA-A alleles as potential haplotype and evolutionary markers. All MER9-LTR sequences were haplotypic when associated with common HLA-A alleles. The number of SNP loci was 2.5 times greater for the solo LTR at the AK locus, which is located closer to the HLA-A gene than the solo or 3′ LTR at the HG locus. Our study shows that the nucleotide variations of the MER9-LTR DNA sequences are additional informative markers in fine mapping HLA-A genomic haplotypes for future population, evolutionary, and disease studies. 相似文献
82.
Jerzy K. Kulski Silvana Gaudieri Annalise Martin Roger L. Dawkins 《Journal of molecular evolution》1999,49(1):84-97
The recent availability of genomic sequence information for the class I region of the MHC has provided an opportunity to
examine the genomic organization of HLA class I (HLAcI) and PERB11/MIC genes with a view to explaining their evolution from
the perspective of extended genomic duplications rather than by simple gene duplications and/or gene conversion events. Analysis
of genomic sequence from two regions of the MHC (the alpha- and beta-blocks) revealed that at least 6 PERB11 and 14 HLAcI
genes, pseudogenes, and gene fragments are contained within extended duplicated segments. Each segment was searched for the
presence of shared (paralogous) retroelements by RepeatMasker in order to use them as markers of evolution, genetic rearrangements,
and evidence of segmental duplications. Shared Alu elements and other retroelements allowed the duplicated segments to be
classified into five distinct groups (A to E) that could be further distilled down to an ancient preduplication segment containing
a HLA and PERB11 gene, an endogenous retrovirus (HERV-16), and distinctive retroelements. The breakpoints within and between
the different HLAcI segments were found mainly within the PERB11 and HLA genes, HERV-16, and other retroelements, suggesting
that the latter have played a major role in duplication and indel events leading to the present organization of PERB11 and
HLAcI genes. On the basis of the features contained within the segments, a coevolutionary model premised on tandem duplication
of single and multipartite genomic segments is proposed. The model is used to explain the origins and genomic organization
of retroelements, HERV-16, DNA transposons, PERB11, and HLAcI genes as distinct segmental combinations within the alpha- and
beta-blocks of the human MHC.
Received: 5 December 1998 / Accepted: 27 January 1999 相似文献