Patent ID: 7803545
Filing Date: 2010-09-28
Classification: C12Q

Abstract:
1. A method for genotyping a target gene sequence said target gene sequence being selected from the group consisting of a −1082 polymorphism in the promoter of the IL-10 gene and a −238 polymorphism in the tumor necrosis factor (TNF) gene promoter comprising: (a) providing a population of induced heteroduplex generator (IHG) molecules corresponding to said target gene sequence, the IHG molecule being a synthetic DNA sequence including at least one nucleotide position which corresponds to a known polymorphic site in the genomic DNA sequence of the target gene sequence and a nucleotide insertion (“identifier”) relative to the genomic sequence at a nucleotide position spaced by a distance of at least one base from the nucleotide position which corresponds to the known polymorphic site and wherein the nucleotide(s) between the nucleotide position which corresponds to the polymorphic site and the identifier are unchanged from the genomic sequence; wherein the at least one identifier comprises an insertion of a base and the IHG molecule is selected to provide improved separation of a resolved plurality of bands by a method comprising comparing the separation obtained using the IHG molecule with the separation obtained using a corresponding IHG in which the identifier is not so spaced; (b) providing a population of the target gene sequence; (c) combining the respective populations of (a) and (b) under conditions suitable for heteroduplex formation, to obtain induced heteroduplexes between the target gene sequence and an IHG molecule corresponding to said target gene sequence; (d) resolving the induced heteroduplexes into bands on a suitable support; and (e) analysing the resolved induced heteroduplexes to determine the genotype of the target gene sequence.