| Large-scale investigations of sequence variation within the human species will provide information about the basis of heritable variation in disease susceptibility and human migrations. New chemistries were developed in this research for performing complex serial enzymatic procedures (including invasive cleavage, ligation, and polymerase extension) on a solid substrate to produce an integrated technology capable of exquisitely sensitive and specific detection of that most subtle of the genetic variations---the single nucleotide polymorphisms (SNPs).; Feasibility of this approach is demonstrated on three model systems: a polymorphic site in codon 158 of the human Apolipoprotein E (ApoE) gene, a set of six single nucleotide polymorphisms in the PTPN1 gene on chromosome 20, and a set of 10 mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene on chromosome 7. This work shows the ability to analyze many different genetic variations in parallel, directly from unamplified human genomic DNA samples, lays the groundwork for the development of high density arrays able to analyze hundreds of thousands or even millions of SNPs. |
