noun. 1  Linguistics A predictable phonetic variant of a phoneme. 2  For example, the aspirated t of top, the unaspirated t of stop, and the tt (pronounced as a flap) of batter are allophones of the English phoneme &sol;t&sol;. 3  or Allophone Canadian A person whose native language is other than French or English.
What is genetic testing? Genetic testing is a type of medical test that identifies changes in chromosomes, genes, or proteins. The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a personâs chance of developing or passing on a genetic disorder. More than 1,000 genetic tests are currently in use, and more are being developed. Several methods can be used for genetic testing: Molecular genetic tests (or gene tests) study single genes or short lengths of DNA to identify variations or mutations that lead to a genetic disorder.
Types of genetic testing. The following information describes the three main types of genetic testing: chromosome studies, DNA studies and biochemical genetic studies. Tests for cancer susceptibility genes are usually done by DNA studies. â. 1  Chromosome studies. 2  Chromosomes are the long stretches of DNA that contain our genes.