Fluorescence-based automated fragment analysis of microsatellite polymorphism within the transmembrane region of the MIC-A gene

Abstract

MHC class I chain-related genes (MIC) are located within the MHC class I region of chromosome 6. Sequence analysis of the MIC-A gene showed a trinucleotide repeat (GCT) microsatellite polymorphism within the transmembrane region. So far, six alleles of the exon 5 of the MIC-A gene, which consist of 4, 5, 6, 9 and 10 repetitions of GCT, or five repetitions of GCT with an additional nucleotide insertion (GGCT), have been identified. Recent works support the findings that MIC-A is associated with several autoimmune diseases. In our work we present a modification of a method used for microsatellite polymorphism detection within the transmembrane region of the MIC-A gene. It is the ALFexpress fluorescence-based automated fragment analysis. We also present the frequencies of MIC-A exon 5 alleles found in the Czech population. We have identified five alleles of the transmembrane region of MIC-A, which comprise 4, 5, 6 and 9 repetitions or five repetitions with an additional nucleotide insertion. The most frequent allele was A5.1 (59.3%) and the less frequent was the allele A5 (20.0%). No A7, A8 or A10 alleles were identified.