Genetic testing refers to an analysis of an individual's genetic information. This is most commonly performed on DNA and focuses on analysis of the region of the individual's genome that is relevant to the particular test.
Genetic tests employ various techniques to measure changes in DNA sequences. The most detailed information is obtained from full DNA sequence analysis. In cases where the tests are for a specific variant(s), a variety of other techniques can be employed. Many genetic tests look for the presence of certain variant alleles (allele refers to one of the two copies of a particular gene; see Glossary) within the coding regions of genes. These are the sequences in DNA that encode proteins. Other genetic tests evaluate DNA alterations in noncoding regions such as introns, DNA sequences flanking genes and intergenic regions of DNA (see Glossary for definition of terms).
A large number of DNA sequence changes can occur. The most common are SNPs (single nucleotide polymorphisms) which are single base substitutions in which one of the 4 bases (A,T,G or C) is changed to one of the other three. These substitutions can change the structure and/or activity of the protein encoded by the gene. These changes can be amino acid replacements, a premature termination of the protein, a linking of part of the native protein to a different protein sequence or have no effect on the encoded protein (a "silent" polymorphism). In cases where a SNP occurs in a non-coding region of the protein it can still affect the final protein structure, and may also affect levels of expression of the gene and other types of gene regulation. Other types of DNA sequence alterations include insertion or deletion of single bases or larger segments of DNA and duplication and inversion of DNA sequences.
When you undergo genetic testing, region(s) of your genome are analyzed for variations that are known or suspected to have certain consequences. At Genomic Express, we only offer genetic tests that have been scientifically and medically validated. That is, there is strong scientific or medical evidence supporting the interpretation of the test result. You can be confident that genetic testing with Genomic Express will provide you with a reliable and understandable test result based on current scientific/medical knowledge and the latest technology.
Genetic tests we currently offer, as well as tests and services that are under development, are described in detail under Genetic Tests and Genomic Services.
A concise list of the genetic tests that we currently offer can also be viewed by following this link: Tests We Offer.