Texas A & M University Animal Genetics Laboratory uses SNP array technology (as they explain on their introduction site) to screen your cat’s DNA for possible mutations responsible for expressing certain traits or making it susceptible to certain diseases.
So, what does SNP stand for? SNP is the short form for Single Nucleotide Polymorphism and is the variation of a single base pair in the DNA sequence between either the members of a species or between the paired chromosomes of an individual. These polymorphisms may affect how organisms develop diseases and respond to chemicals and drugs. SNPs are, therefore, of great value in biomedical research and drug development. SNP detection and genotyping can be used to explain and diagnose many diseases, to study the variation in drug responses, to establish the origin of biological material and to study the relatedness between individuals.
Once it has been established that a SNP pattern is associated with a particular disease, or traits, such as coat color or coat length, etc. they can use SNP microarray technology to test an individual for that disease/trait expression pattern to determine whether the individual is susceptible to (at risk of developing) that disease or express/carries the trait. When genomic DNA from an individual is hybridized to an array loaded with various SNPs, the sample DNA will hybridize with greater frequency only to specific SNPs associated with that individual. Those spots on the microarray will then fluoresce with greater intensity.
Please, also look at the following animation illustrating and explaining the technology