DNA microarrays of networked oligonucleotides

A method for fabricating microarrays, the method comprising:

• a) providing a first oligonucleotide having a length of about 40 bases or greater,
• b) crosslinking said first oligonucelotide with a chemically unmodified, single-stranded, second oligonucleotide to form a network,
• c) affixing said network to a substrate by predominantly non-covalent means.

A method for detecting genetic polymorphism, the method comprises:

• a) providing an array comprising a number of biosites with a network of cross-linked oligonucleotides, in which a number of said networked oligonucleotides are non-covalently associated with a substrate;
• b) hybridizing target nucleic acid sequences to said first or second set of oligonucelotides to attain a hybridization sensitivity of comparable quality as that achieved with polymerase chain reaction products.