Germany
— Researchers in Germany have found that
variations in a gene related to male sex hormones may be
at the root of male-pattern baldness, the most common
form of hair loss. The culprit is the androgen receptor
gene, and it dwells on the X chromosome, which all men
inherit from their mothers.
Experts have long
believed that hair loss in inherited. But the new
research, to be published in the American Journal of
Human Genetics, is the first to identify a specific gene
that may be involved, according to the study
authors.
Other, yet-unidentified
genes are likely involved in male-pattern baldness,
possibly including ones handed down by fathers. But the
new findings highlight the importance of mom's side of
the family when it comes to a man's hairline, according
to the study authors, led by Dr. Markus M. Nothen of the
University of Bonn.
A young man concerned
about the future of his hair may do better to look toward
his maternal grandfather's hair history rather than his
father's, according to the researchers.
Their study included 95
German families in which at least two brothers had begun
losing their hair before the age of 40. Using blood
samples from these men and other family members without
early hair loss, the researchers found that a particular
variant in the androgen receptor gene occurred much more
frequently among men with early male-pattern baldness
compared with men who retained a full head of hair past
the age of 60.
The androgen receptor
gene helps govern the workings of male sex hormones
(androgens), such as testosterone. Though these hormones
promote the growth of body and facial hair, on the scalp
excess androgens may cause hair loss. It's possible,
according to Nothen and his colleagues, that the suspect
gene variant creates a greater number of androgen
receptors in the scalp -- and therefore stronger androgen
activity.
The researchers say they
are continuing to hunt down the other genes involved in
early-onset male-pattern baldness. Scientists hope that
getting at the genetic roots of hair loss will eventually
spawn better baldness treatments or a cure.
