{"title":"Five new polymorphisms in the complement C7 gene and their association with C7 deficiency.","authors":"B A Fernie, M J Hobart","doi":"10.1159/000019107","DOIUrl":null,"url":null,"abstract":"<p><p>Five new polymorphisms in the C7 gene are described: 2 in intron 1, and 1 each in introns 7, 8 and 15. Four of these are single nucleotide exchanges, while the fifth is a T insertion at 10 sequential Ts. Allele frequency data are presented for intervening sequence (IVS)1+ 55 in 6 normal population groups. We present new and updated data in these populations on a previously described C7 polymorphism in exon 13 (cDNA 1792 A/T). We also report the extended haplotypes associated with C7 deficiency for which marker investigation is a useful, and in some cases vital, adjunct to the identification of the gene defects. Almost without exception, a particular haplotype is associated with a particular mutation causing the deficiency state. Haplotyping is especially useful where polymerase chain reaction failure on one chromosome could be a cause for difficulties in detecting a molecular defect due to heterozygosity for large deletions or unidentified variations at the locations of the primers.</p>","PeriodicalId":77124,"journal":{"name":"Experimental and clinical immunogenetics","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000019107","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Experimental and clinical immunogenetics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1159/000019107","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 4
Abstract
Five new polymorphisms in the C7 gene are described: 2 in intron 1, and 1 each in introns 7, 8 and 15. Four of these are single nucleotide exchanges, while the fifth is a T insertion at 10 sequential Ts. Allele frequency data are presented for intervening sequence (IVS)1+ 55 in 6 normal population groups. We present new and updated data in these populations on a previously described C7 polymorphism in exon 13 (cDNA 1792 A/T). We also report the extended haplotypes associated with C7 deficiency for which marker investigation is a useful, and in some cases vital, adjunct to the identification of the gene defects. Almost without exception, a particular haplotype is associated with a particular mutation causing the deficiency state. Haplotyping is especially useful where polymerase chain reaction failure on one chromosome could be a cause for difficulties in detecting a molecular defect due to heterozygosity for large deletions or unidentified variations at the locations of the primers.