Genetic markers are particular parts of the genome that differ, or have polymorphisms, from one individual to another. They are sequences with a specific location on a chromosome that can be used to identify individuals or species. These variants might appear as greater structural changes, insertions or deletions of genetic material, or single nucleotide changes (SNPs).[1] Scientists can map these markers to particular genes or genomic areas and examine how they relate to particular traits or situations by discovering and researching these markers.[2]
The study of genetics has advanced greatly throughout time, providing priceless insights into the intricate nature of human biology. Genetic markers have become effective instruments for researching human variation, detecting disease risk factors, and comprehending the evolutionary past of living beings among the different tools and methods used in genetic research.[3]
Types of genetic markers
- Single Nucleotide Polymorphisms (SNPs): The most prevalent form of genetic variation in humans is known as single nucleotide polymorphism, best known for their acronym SNP. Certain diagnostic tools entail the replacement of a single nucleotide at a predetermined location within the DNA sequence. SNPs can affect phenotypic features such as treatment responsiveness, illness susceptibility, and gene activity.[4]
- Insertions and Deletions (Indels): Indels, or insertions and deletions, are genetic markers that are identified by the insertion or deletion of a few nucleotides from the DNA sequence.[5] These indicators can alter protein structure, interfere with gene activity, and cause a number of diseases and disorders.
- Copy Number Variations (CNVs): CNVs stand for copy number variations, which are variations in the number of copies of a specific DNA section.[5] These markers play a crucial role in genetic diversity and disease vulnerability and may entail the duplication or deletion of vast DNA segments.
- Microsatellites: Microsatellites are repeating DNA sequences made up of brief nucleotide motifs, sometimes referred to as short tandem repeats (STRs).[6] These longer markers, which exhibit significant interindividual variation, have been used extensively in forensic and population genetic research.
Applications of genetic markers
Genetic markers have multiple applications in modern life, even beyond medicine and agriculture; our understanding of the genetic basis of numerous diseases has been fundamentally altered by the discovery of genetic markers. Scientists are able to identify people who are more vulnerable to certain ailments and create specialized prevention plans by linking particular markers to those conditions,[7] as well as being able to prevent certain diseases through preemptive medicine therapy.
Also, genetic markers offer useful information on the genetic diversity and evolutionary background of populations, making it possible for researchers to identify migration patterns, determine ancestral origins, and reassemble the human evolutionary tree.[8] Pharmacogenomics, the study of how genetic diversity affects a person's reaction to medications, relies heavily on genetic markers.[9] Healthcare providers have been able to customize pharmaceutical regimens and improve treatment outcomes by identifying specific markers linked to drug efficacy or metabolism. Lastly, forensic investigations frequently use genetic markers, such as microsatellites, for DNA analysis and identification.[10] These identifiers are essential in establishing a person's identification, connecting suspects to crime sites, and providing evidence in criminal cases.
Genetic markers and genealogy
Genetic markers play a pivotal role in the realm of DNA testing for genealogy. DNA testing relies on these markers to provide insight into one's genetic heritage. Comparing an individual's genetic markers with databases of known markers and populations enables the identification of shared segments, revealing distant and close relatives. These markers provide a roadmap through time, highlighting migration patterns and genetic mixing, and helping genealogists construct intricate family trees.
Genetic markers and ethical challenges
Despite the enormous promise for scientific and medical improvement that genetic markers present, their usage also poses a number of ethical questions and risks involved.[11] To ensure the ethical and appropriate use of genetic marker research, concerns about privacy, genetic prejudice, and consent must be addressed, as well as making sure that the advantages genetic markers bring to the society are distributed fairly.
Explore more about genetic markers
- What Exactly is a Centimorgan? An Introduction to the Science of DNA Testing on the MyHeritage Knowledge Base
- How Does DNA Matching Work? on the MyHeritage Knowledge Base
- DNA Basics Chapter 5: How DNA testing works on the MyHeritage Blog
References
- ↑ Ismail, S., & Essawi, M. (2012). Genetic polymorphism studies in humans. Middle East Journal of Medical Genetics, 1(2), 57-63.
- ↑ Schuler, G. D., Boguski, M. S., Stewart, E. A., Stein, L. D., Gyapay, G., Rice, K., ... & Hudson, T. J. (1996). A gene map of the human genome. Science, 274(5287), 540-546.
- ↑ Hackinger, S., & Zeggini, E. (2017). Statistical methods to detect pleiotropy in human complex traits. Open biology, 7(11), 170125.
- ↑ Rafalski, A. (2002). Applications of single nucleotide polymorphisms in crop genetics. Current opinion in plant biology, 5(2), 94-100.
- ↑ 5.0 5.1 Bhattramakki, D., Dolan, M., Hanafey, M., Wineland, R., Vaske, D., Register, J. C., ... & Rafalski, A. (2002). Insertion-deletion polymorphisms in 3′ regions of maize genes occur frequently and can be used as highly informative genetic markers. Plant molecular biology, 48, 539-547.
- ↑ Stanley, U. N., Khadija, A. M., Bukola, A. T., Precious, I. O., & Davidson, E. A. (2020). Forensic DNA profiling: autosomal short tandem repeat as a prominent marker in crime investigation. The Malaysian journal of medical sciences: MJMS, 27(4), 22.
- ↑ Arnett, D. K., Baird, A. E., Barkley, R. A., Basson, C. T., Boerwinkle, E., Ganesh, S. K., ... & O’Donnell, C. J. (2007). Relevance of genetics and genomics for prevention and treatment of cardiovascular disease: a scientific statement from the American Heart Association Council on Epidemiology and Prevention, the Stroke Council, and the Functional Genomics and Translational Biology Interdisciplinary Working Group. Circulation, 115(22), 2878-2901.
- ↑ Ralph, P., & Coop, G. (2013). The geography of recent genetic ancestry across Europe. PLoS biology, 11(5), e1001555
- ↑ Goldstein, D. B. (2009). Common genetic variation and human traits. New England journal of medicine, 360(17), 1696.
- ↑ Hagelberg, E., Gray, I. & Jeffreys, A. Identification of the skeletal remains of a murder victim by DNA analysis. Nature 352, 427–429 (1991).
- ↑ Issa, A. M. (2000). Ethical considerations in clinical pharmacogenomics research. Trends in Pharmacological Sciences, 21(7), 247-249.