We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Positional Cloning?

Mary McMahon
Updated May 21, 2024
Our promise to you
All The Science is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At All The Science, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Positional cloning is a technique that is used in genetic screening to identify specific areas of interest in the genome, and then determine what they do. This type of screening is sometimes referred to as reverse genetics, because researchers start by figuring out where a gene is, and then they determine what it does, in contrast with methods which start by determining the function of a gene and then finding it in the genome. Genes related to conditions such as Huntington's Disease and cystic fibrosis have been identified with this technique.

In this process, researchers find an area of interest on the genome by looking for genetic markers. They often take advantage of databases that collect information about people with medical conditions so that they can identify common traits that can be used to narrow down an area of the genome that might reveal useful information. Once markers have been found, a researcher can clone and investigate the area of interest to determine what it does. Positional cloning can also be used to screen specific individuals for genetic issues.

This technique depends on a very extensive and well equipped lab that a researcher can use to investigate the genome and experiment with mutations. It also relies on a genome database that researchers can use to compare their results with the genomes of normal individuals, along with individuals who have various mutations and medical conditions. In organisms like plants and fruit flies, a researcher can actually stimulate the creation of mutations with genetic manipulation to learn more about how an area of the genome functions. Such experimentation in humans is not ethical, forcing researchers to compare the information they find with genetic samples, looking for signs of mutations and the way in which mutations express themselves.

Using procedures like this, researchers can map out the genome and slowly but steadily find out what each area of it does. The more information researchers find, the easier their work is, as they can start to find connected markers and traits that interact with each other. Analysis of the genome will also allow researchers to come up with tests that can be used to look for specific inherited conditions and mutations. These tests can be used to screen fetuses for potential birth defects, and to test children and adults for underlying genetic conditions that could manifest later in life.

Like many types of research connected to the genome, positional cloning can sometimes attract controversy. By finding the sites of specific genetic conditions, researchers lay the groundwork for potential treatments and cures, but they also raise questions about genetic testing and how it can be used. For example, with a genetic test to look for the genes that are related to Huntington's Disease, parents might opt to test a fetus during pregnancy and abort it if the test is positive, a choice that could raise uncomfortable ethical questions.

All The Science is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Mary McMahon
By Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a All The Science researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Discussion Comments

By anon348535 — On Sep 18, 2013

@everyone: Er, no. Positional cloning is a technique to work out what gene causes a specific phenotype.

The only time it is used in humans is when a rare genetic disease has an unknown cause. Positional cloning is the technique used to work out which gene is causing the problem.

This type of "cloning" does not produce clones of organisms (which is often viewed as controversial) but clones of small segments of DNA which usually do not even contain genes (cannot even imagine how this would be controversial).

By miriam98 — On Apr 30, 2011

@SkyWhisperer- Personally, I’m all for progress—especially in medicine. What we learn from this research will help doctors find cures for diseases like cancer. A doctor could use these techniques to zero in on tumor suppressor genes, for example, which are markers for cancer. Sure, it wouldn’t be any fun to find out you had those markers in your body, but at least knowing what you were dealing with would give you a fighting chance to beat it.

By SkyWhisperer — On Apr 29, 2011

@MrMoody - Cloning on any scale is going to be controversial nevertheless. Anytime I hear about cloning I think about the Jurassic Park dilemma—just because we can do something, should we? This type of positional cloning lets you know things that perhaps you would prefer not to know.

By MrMoody — On Apr 26, 2011

@Catapult – I think they actually do clone but on a smaller scale. Once they find the gene pool they’re looking for, they clone that for further analysis. It’s not as bad as cloning a human or what you see in some science fiction movies.

By Catapult — On Feb 24, 2011

At first glance I thought the name would refer to an actual type of cloning, as in a type of replicating something. I suppose cloning has become just a term for various things involved in using a genetic map, but I find that a bit confusing.

Mary McMahon

Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a...

Learn more
All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.