Hair cloning

Key takeaways

Hair cloning belongs to engineering; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Hair cloning to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Hair cloning from memory before moving on to harder problems.

Reference excerpt

Hair cloning, or hair multiplication, is a proposed technique to counter hair loss. The technology is in its early stages, but multiple groups have demonstrated pieces of the technology at a small scale, with a few in commercial development. Scientists previously assumed that in the case of complete baldness, follicles are completely absent from the scalp, so they cannot be regenerated. However, the follicles are not entirely absent, as there are stem cells in the bald scalp from which the follicles naturally arise. The behavior of these follicles is suggested to be the result of progenitor cell deficiency in these areas. The basic idea of hair cloning is that healthy follicle cells or dermal papillae can be extracted from the subject from areas that are not bald and are not suffering hair loss. They can be multiplied (cloned) by various culturing methods and the new cells can be injected back into the bald scalp, where they would produce healthy hair.

Research

Early trials One of the first companies to begin experimenting with hair cloning was Intercytex. Intercytex tried to clone new hair follicles from the stem cells harvested from the back of the neck. They hoped that if they multiplied the follicles and then implanted them back in the scalp in the bald areas, they would be successful in regrowing the hair itself. In 2008, Intercytex interpreted that they failed in fully developing the hair cloning therapy and decided to discontinue all research. The first time scientists were able to grow artificial hair follicles from stem cells was in 2010. Scientists at the Technische Universität Berlin in Germany, with Intercytex and several other research teams, took animal cells and created follicles by using them. As a result, they produced follicles "thinner than normal". They were able to clone one or two follicles from an extracted hair. Aderans Research Institute, a Japanese company, worked on what they called the "Ji Gami" process, which involved the removal of a small strip of the scalp, which is broken down into individual follicular stem cells. After the extraction, these cells are cultured and injected back into the bald areas of the scalp. The trials continued in 2012. Aderans decided to discontinue the funding of its hair multiplication research in July 2013.

University of Pennsylvania In 2012, scientists from the University of Pennsylvania School of Medicine published their own findings regarding hair cloning. During their investigation, they found that non-bald and bald scalps have the same number of stem cells, but the progenitor cell number was significantly depleted in the case of the latter. Based on this, they concluded that it is not the absence of the stem cells that are responsible for hair loss but the unsuccessful activation of said cells.

Development In 2015, initial trials for human hair were successful in generating new follicles, but the hairs grew in varying directions when implanted in lab mice. In 2016, scientists in Japan announced they had successfully grown human skin in a lab. The skin was created using induced pluripotent stem cells, and when implanted in lab mice, the skin grew hairs successfully. The group has formed partnerships with Organ Technologies and Kyocera Corporation to commercially develop the research. In July 2019, a researcher from San Diego–based Stemson Therapeutics, partnered with UCSD, successfully grew his own follicles on lab mice using iPSC-derived epithelial and dermal cell therapy. The hair was aligned properly with a 3D-printed biodegradable shaft. The hairs were permanent and regenerated naturally. Stemson therapeutics closed operations in December 2024. In October 2022, researchers from the Japan-based Yokohama National University successfully cloned fully-grown hair follicles for the first time in history on lab mice. In February 2026, Takashi Tsuji, a senior researcher at Riken and chairperson of OrganTech, and his team of researchers including Koh-ei Toyoshima, Miho Ogawa, and Ayako Tsuchiya discovered a key missing 3rd cell type for hair cloning (Identified as PDGFRα⁺ CD34⁺ Sca1⁺ mesenchymal) besides epithelial stem cells and dermal papilla cells. These cells from the dermal condensate region act like "cellular conductors", orchestrating the entire follicle formation process, enabling 100% efficient lab-grown hair follicles. These bioengineered follicles produced 3mm hair shafts and cycled naturally for 68 days when tested on lab mice.

See also Hair loss Follicular unit transplantation

References

Further reading Cell Therapy for Hair Loss Hair restoration Haarklinik (in German)

Worked examples

Example 1 — a first encounter with Hair cloning

Start with the simplest possible case. Write down what Hair cloning claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Hair cloning before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Hair cloning ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Hair cloning

In research: Hair cloning appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Hair cloning in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Hair cloning is common in secondary-school and first-year university syllabi. It links to neighbouring topics Human hair, Tissue engineering, Trichology, so understanding it makes those chapters shorter.
In everyday life: Look for Hair cloning outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Hair cloning in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Hair cloning means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Hair cloning out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Hair cloning in simple terms?

Hair cloning, or hair multiplication, is a proposed technique to counter hair loss. The technology is in its early stages, but multiple groups have demonstrated pieces of the technology at a small scale, with a few in commercial development.

Why does Hair cloning matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Hair cloning?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Hair cloning.