Refuting earlier claims, increased hair growth happens with activation of the Lhx2 gene according to findings by Leif Carlsson’s research team at Umeå University.
Hair is formed in special follicles in the skin that are formed during fetal development. New hair is generated in the hair follicle by continually undergoing phases of recession, rest, and growth throughout life. The length of the hair is determined by the duration of the growth phase. After growth, hair formation ceases and the follicle enters a rest period after which a new growth period starts and old hair is lost. This complex regulation may enable seasonal adjustments. The scientists proved that Lhx2 is involved in the formation of hair, and it is the gene that regulates hair growth.
Contrasting previous findings, Carlsson showed that Lhx2 is primarily expressed outside the bulge region of the hair follicle where the stem cells exist. The Umeå researchers also found that Lhx2 is necessary for the hair follicle’s growth phase to proceed and for the hair follicle’s structuring. Moreover, transgenic expression of Lhx2 after birth is sufficient to activate the growth phase and stimulate hair growth. Lhx2 is expressed periodically, primarily in precursor cells that are distinct from the cells in the bulging region of the follicles, and the gene is necessary for hair to be formed and to grow.

Resource: www.medfak.umu.se