Biotech Articles
Publish Your Research Online
Get Recognition - International Audience

Request for an Author Account   |   Login   |   Submit Article

Genetic Marker: Its Definition, Introduction, Background and Types

BY: Muniba Safdar | Category: Genetics | Submitted: 2011-03-14 18:38:48
       No Photo
Article Summary: "What is genetic marker? A genetic marker is defined as a specific gene or DNA sequence that produces a detectable trait with a known location on a chromosome and that can be used to study family and population, identification of cells, species or individual. Genetic marker can also be described as a variation. It may be a short .."

Share with Facebook Share with Linkedin Share with Twitter Share with Pinterest Email this article


"A genetic marker is defined as a specific gene or DNA sequence that produces a detectable trait with a known location on a chromosome and that can be used to study family and population, identification of cells, species or individual".


Genetic marker can also be described as a variation (or a change that may be arising due to alteration or mutation in the chromosome locus). It may be a short sequence of DNA, for example single nucleotide polymorphism or SNP (genetic variation in a DNA sequence that occurs when a single nucleotide in a genome is altered; SNPs are usually considered to be point mutations that have been evolutionarily successful enough to recur in a significant proportion of the population of a species), or a long sequence, such as mini-satellites (is a section of DNA that consists of a short series of bases 10-60 bp).


In the past, most organisms were limited in gene mapping (is defined as graphical representation of the arrangement of genes on a chromosome) by genetic markers these includes genes that translate observable features, for example blood types or seed shapes.


There are numerous types of genetic markers that are commonly used;

• Simple Sequence Length Polymorphism or SSLP: This is used as a genetic marker with polymerase chain reaction or PCR (used to produce multiple copies of DNA). It is a type of polymorphism (is the existence of two or more forms of individuals within the same animal species) and repeated sequences in intergenic regions of DNA. Genetic variation between two individuals can be understood by using length of SSLPs.

• Restriction Fragment Length Polymorphism or RFLP:
It is a technique that uses variations in DNA sequences. In this technique, sample of DNA is broken into small pieces with the help of restriction enzyme. Then these small pieces will be separated according to their lengths by gel electrophoresis (that separates molecules on the basis of their rate of movement through a gel). RFLP is an important tool in localizing genes for genetic disorder (), genome mapping, finding of risk for disease, and paternity testing (is the use of genetic fingerprinting to determine whether two individuals have a biological parent-child relationship).

• Amplified Fragment Length Polymorphism or AFLP: It is a PCR-base tool. It is used in different fields such as genetics, DNA fingerprinting (or DNA testing, DNA typing is a technique employed by forensic scientists to assist in the identification of individuals by their respective DNA profiles) and genetic engineering.

• Random Amplification of Polymorphic DNA or RAPD:
It is a type of polymerase chain reaction but in this case DNA segments that are amplified would be random. It has been used to trace the phylogeny (is the sequence of events involved in the evolutionary development of a species or taxonomic group of organisms) of various animals and plants.

• Single Nucleotide Polymorphism or SNP:
It is a segment of DNA sequence in the genome. In other words, it is a genetic variation that occurred when a single nucleotide A, T, C, or G is altered in a genome. Most commonly SNPs have only two alleles.

• Variable Number Tandem Repeat or VNTR:
It is located in a genome where nucleotide sequence is arranged as tandem repeat. These repeats can be found on many chromosomes. VNTR analysis is useful and important in genetics, forensics, biology research and DNA fingerprinting.

• Short Tandem Repeat or STR: It occurs in DNA when two or more nucleotides are repeated. These repeated sequences are immediately adjacent to each other. In forensic cases, STR analysis is used for determining genetic profiles.

About Author / Additional Info:

Search this site & forums
Share this article with friends:

Share with Facebook Share with Linkedin Share with Twitter Share with Pinterest Email this article

More Social Bookmarks (Digg etc..)

Comments on this article: (1 comments so far)

Comment By Comment
2013-11-17 15:13:24 724
Salam! The article is informative but you have concentrated on just DNA markers. In fact, DNA markers are a sub-category of genetic markers while as the latter includes morphological, cytological and biochemical markers as well. Regards!

Leave a Comment   |   Article Views: 26087

Additional Articles:

•   Are Probiotics the Cure for Digestive, Mental & Neurological Disorders?

•   Cellphone Radiation - Health Effects and Means of Protection

•   Cloning in the Dairy Industry for Improving Dairy Production

•   Greiner Bio-One in Monroe, NC Opens New Warehouse Facility

Latest Articles in "Genetics" category:
•   The Science and History of Genetics. How It Predicts the Genetic Code

•   Telomeres: Is It Responsible For Ageing and Cancer?

•   Human Genetic Engineering,its Methods and Ethics

•   Gene Mutation And Cancer

•   DNA Technology Used in Forensics

•   DNA Fingerprinting: Uses and Methods Involved

•   Treatment of Genetic Diseases by Gene Therapy

•   Human Intelligence and Genetics

•   Ethical Issues Related to Human and Animal Cloning

•   Mitochondrial DNA and Forensic

•   DNA Footprinting and Gene Sequencing

•   Biotechnology and Types of Cloning

•   Designer Babies:Method and Ethical Issues

•   Prenatal Diagnosis: Non-invasive and Invasive Techniques

•   What are the Benefits of Genetic Engineering?

•   The Advantages and Disadvantages of Genetic Engineering in Humans

•   Types of Genetic Disorders

•   Bovine Somatotropin: A Growth Hormone

•   Advantages and Disadvantages of Genetically Modified Food

Important Disclaimer: All articles on this website are for general information only and is not a professional or experts advice. We do not own any responsibility for correctness or authenticity of the information presented in this article, or any loss or injury resulting from it. We do not endorse these articles, we are neither affiliated with the authors of these articles nor responsible for their content. Please see our disclaimer section for complete terms.
Page copy protected against web site content infringement by Copyscape
Copyright © 2010 - Do not copy articles from this website.

Agriculture Bioinformatics Applications Biotech Products Biotech Research
Biology Careers College/Edu DNA Environmental Biotech
Genetics Healthcare Industry News Issues Nanotechnology
Others Stem Cells Press Release Toxicology  

  |   Disclaimer/Privacy/TOS   |   Submission Guidelines   |   Contact Us