| PerkinElmer Genetics performs routine clinical analysis to support the newborn screening program. The Molecular Division supports the program with second-tier analysis of specimens that show putative positive results following initial analysis. Initial analysis in the program searches for abnormally high levels of critical chemicals in the blood of the newborns. Many disorders that are assayed for have common genetic abnormalities often referred to as mutations. |
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To detect these common mutations, a procedure called polymerase chain reaction (PCR) is employed. PCR is able to specifically amplify a small region of DNA that contains one of these common mutations. This small region of DNA is then analyzed to determine if the mutation is present. In our laboratory, cutting-edge technology is used to determine the presence or absence of specific mutations. The technology allows the identification of mutations in a matter of minutes, where older traditional methods would require numerous steps and up to an entire day to generate equivalent data. This technology allows us to provide critical genetic data within minutes, allowing physicians to diagnose their patients.
What is a gene?
A gene is a specific section of DNA that is responsible for a trait. Genes are located upon chromosomes. Traits such as eye color or how our body breaks down a particular chemical are controlled by genes.
What is a mutation?
DNA is composed of four chemical building blocks (adenine, cytosine, thymine, guanine) that must be maintained in a strict order to function properly. A gene could be thought of as a string of beads consisting of these four building blocks. If the sequence of these building blocks is changed, perhaps a adenine where a guanine is typically found, this may result in a disease causing mutation. A mutation is a change in the chemical sequence of the DNA.
How does polymerase chain reaction specifically copy a small sequence within a gene?
Polymerase chain reaction functions as a chemical "photocopy" machine by taking advantage of how nature devised DNA to be copied within cells. By artificially directing DNA replication in a test tube, a small section of a gene can be copied many thousands of times until there are adequate quantities for analysis.