Japan mouse study
finds hair-loss gene
TOKYO, May 26, 2009 (AFP) - Experiments on mice have revealed a
gene that is linked to early hair loss, a Japanese researcher said
Tuesday 26 May, sparking hopes for a treatment to prevent thinning
and baldness in humans.
The research team found that the absence of a gene known as Sox21
-- which it said is shared by humans and mice -- can lead to early
hair loss.
The scientists biologically engineered mice by blocking the gene
and found that the rodents started losing hair on their heads about
15 days after birth and became completely naked a week later.
"Normally, new hair appears right after old hair falls out," said
Yumiko Saga, a mammalian development professor at the National
Institute of Genetics.
"But the hair of these mice fell out very early, making their bald
periods longer," she told AFP, adding that although the mice
started to grow new fur, the replacement hair also kept falling out
quickly.
The Sox21 gene has in the past been shown to be linked to the
formation of nerve cells, but the Japanese study was the first to
indicate its function in ensuring hair retention, she said by
telephone.
"It is entirely possible that the gene is also a cause of thinning
hair" among humans, Saga said.
The study, jointly conducted with Hideyuki Okano, professor at the
School of Medicine at Tokyo's Keio University, found that the lack
of the gene leads to the improper formation of cuticles, the outer
layer of hair.
"Cuticles usually have a scaled structure, locking hair in the
scalp," said Saga. Blocking the gene in the mice meant that their
cuticles lacked this structure, making the hair fall out more
quickly, Saga said.
The study could lead to the development of a medical treatment
against thinning hair, Saga said, but she added that she had no
immediate plans for further research to develop a human
application.