Description: A genetic marker is a gene or DNA sequence with a known location on a chromosome that is used as a reference to identify the position of other genes. These markers can be nucleotide sequences, such as single nucleotide polymorphisms (SNPs), or longer sequences that may include DNA repeats. Genetic markers are fundamental in genetics and molecular biology, as they allow researchers to track the inheritance of specific traits and study genetic variability within a population. Their use has expanded with the advancement of bioinformatics, which facilitates the analysis and interpretation of large volumes of genetic data. The ability to identify and map these markers has revolutionized genetic research, enabling the identification of genes associated with diseases, the improvement of crops in agriculture, and the understanding of species evolution. In summary, genetic markers are essential tools in modern genetic research, providing a framework for the study of inheritance and genetic diversity.
History: The concept of genetic markers began to develop in the 1980s with the advancement of molecular biology techniques. In 1983, the discovery of the polymerase chain reaction (PCR) by Kary Mullis allowed for the amplification of specific DNA sequences, facilitating the identification of genetic markers. By the late 1990s, the Human Genome Project propelled research into genetic markers, with the goal of mapping all human genes. This effort culminated in 2003 when the first draft of the human genome was completed, enabling the identification of numerous genetic markers associated with various diseases.
Uses: Genetic markers are used in various applications, including medical research to identify genes related to hereditary diseases, in agriculture to improve crops through the selection of desirable traits, and in population studies to understand genetic diversity and evolution. They are also fundamental in personalized medicine, where they are used to predict a patient’s response to certain treatments based on their genetic profile.
Examples: An example of a genetic marker is the SNP rs12979860, which has been associated with the response to hepatitis C virus treatment. Another example is the DNA marker used in paternity tests, which compares specific sequences between the father, mother, and child to determine biological relationships. In agriculture, genetic markers are used to identify pest-resistant corn varieties.
