Androgens, hair loss and eugenics: a tale of discovery and
American social history
Shanti M. Ayob and Andrew G. Messenger
Dermatology Department, Royal Hallamshire Hospital, Sheffield, UK
Correspondence
: Shanti M. Ayob, Dermatology Department, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, United Kingdom. Tel.:
+44 114 2712442, Fax: +44 114 2713763, e-mail: shanti.ayob@sth.nhs.uk; lblace@yahoo.com
Key words:
androgenetic alopecia – androgens – James Hamilton – male
balding – testosterone
Accepted for publication 19 March 2015
According to Hippocrates ‘eunuchs are not subject to gout nor do
they become bald’ (Aphorisms VI, 28). The explanation for this
insight into male balding eventually emerged over two millennia
later from the work of the American anatomist James B Hamilton
(Fig. 1), published in the American Journal of Anatomy in 1942
(1). (The full text is freely available via http://onlinelibrary.wi-
ley.com/doi/10.1002/aja.1000710306/pdf). Prior to this, it was well
known that balding is an inherited trait and that it is more com-
mon in men than women (2,3). It was also known that scalp hair
loss occurs in women with androgen-secreting tumours. But it
was Hamilton who made the key connection that male balding
requires both a genetic predisposition and testosterone.
Hamilton studied 104 men with testicular insufficiency. Of
these 20 men, who were aged between 19 and 69 at the time of
examination, had developed testicular insufficiency prepubertally:
10 naturally and referred to as ‘eunuchoid’ and 10 due to castra-
tion. Thirty-four men, aged 21 to 57 years of age, had been cas-
trated during adolescence and 50 (aged between 30 and 61) after
the age of 20. He observed that men who acquired testicular
insufficiency before puberty retained a prepubertal frontal hairline
and none developed balding. Those castrated during adolescence
showed only minor fronto-temporal hair loss without vertex bald-
ing. In men castrated later in life, some showed advanced degrees
of balding but in a subgroup of 12 men who were losing hair at
the time of castration, none showed progression of hair loss when
re-examined one year later. In the decisive experiment, he then
treated 12 men in the prepubertal testicular insufficiency group
with testosterone. Four of these men developed typical male bald-
ing, and he was able to link the individual response or non-
response to testosterone to the family history of balding. In two
subjects, he reported that the progression of hair loss ceased when
testosterone treatment was suspended but continued when treat-
ment was resumed.
Hamilton subsequently made a number of other important
observations on androgens and human hair growth. Using a simi-
lar subject group, he confirmed that beard growth is androgen-
dependent and that the regression of established beard growth fol-
lowing castration was incomplete and influenced by the duration
of beard growth prior to surgery
–
the later this was performed,
the less the regression (4). He measured the time course and vol-
ume of secondary sexual hair growth in gonadally intact men and
women and showed the time course varied in different regions of
the skin. Thus, pubic and axillary hair growth in both sexes peaks
in the mid-twenties and then declines, whereas male beard growth
is not maximal until the thirties and remains almost unaltered
thereafter (4). His other lasting legacy is the first classification of
male balding (5) (Fig. 2) which, modified by O’Tar Norwood (6),
is still in widespread use as the Hamilton
–
Norwood classification.
How did Hamilton gain access to such a large number of men
who had been castrated? This is not disclosed in the body of the
paper, but there is a clue in the brief acknowledgement in the
footnote to the first page of his 1942 paper. Here, he thanks
Charles Hawke (the superintendent) and staff of the Winfield
State Training School. This establishment was a public institution
for the mentally disabled in Kansas. Along with 27 other North
American states, Kansas has a colourful and infamous history of
enforced sterilisation of the mentally impaired. This practice was
legalised in Kansas in 1913 and continued into the early 1950s
(7). The Winfield State Training School opened in 1881 as the
Kansas State Asylum for the Education of Idiotic and Imbecile
Youth, before being renamed in 1920. In 1893, the incumbent
superintendent, a physician supporting the eugenics movement,
Figure 1.
James B. Hamilton, 1954. Photographer: Philip J. Fleury. Image obtained
from the US National Library of Medicine.
412
ª
2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Experimental Dermatology
, 2015,
24
, 412–413
DOI: 10.1111/exd.12702
www.wileyonlinelibrary.com/journal/EXD
Commentary: My Favourite Historical Paper
which strived for medical improvement of the population, intro-
duced castration as a method of preventing masturbation (7)
.
Despite initial local uproar, by the 1910s, sterilisation had become
a common method for behaviour control of the institutionalised
mentally disabled. It is clear from other publications that for some
inmates, sterilisation meant surgical castration, not just vasectomy.
In table 3 of Hamilton’s 1969 paper on the effect of castration on
longevity (8), he documents the number of inmates who were
castrated per annum at the Winfield State Training School from
1895 to 1950
–
a total of 322 men.
The success of hair transplantation demonstrates that the
response of scalp hair follicles to androgens is determined within
the follicle. Publications in this journal have discussed recent
research exploring the role of prostaglandins, proteoglycans and
growth factors in this process (9,10). Nevertheless, Hamilton’s
observations and experiments remain of fundamental importance
to our understanding of the biology of male balding and have not
been diminished by later studies showing that the testosterone
metabolite dihydrotestosterone, rather than testosterone itself, is
responsible for driving male hair loss. His observation that balding
was not reversed by castration or withdrawal of testosterone has,
to some extent, been challenged by the results of clinical trials
with 5
a
-reductase inhibitors, but it is clear that the degree of
reversibility is severely limited
–
androgens are instrumental in
causing follicular regression in male balding but, once this has
taken place, the absence of androgens achieves, at best, only a
minor degree of reversal.
Attitudes to the conduct of medical research and the treatment
of subjects have changed since 1942, and it would now be difficult
if not impossible to repeat Hamilton’s study. We salute the major
contribution James Hamilton made to human hair biology. At the
same time, we are indebted to the subjects of his research who,
prior to his involvement, had suffered what we would now con-
sider unacceptable and cruel treatment by those responsible for
their care.
Acknowledgement
SMA and AGM co-wrote and reviewed the paper.
Conflict of interests
The authors have declared no conflicting interests.
References
1
Hamilton J B. Am J Anat 1942:
71
: 451
–
480.
2
Osborn D. J Hered 1916:
7
: 347
–
355.
3
Snyder L H, Yingling H C. Hum Biol 1935:
7
:
608
–
615.
4
Hamilton J B. Age, sex and genetic factors in
the regulation of hair growth in men: a compar-
ison of Caucasian and Japanese populations. In:
Montagna W, Ellis R A, eds. The Biology of Hair
Growth. New York: Academic Press, 1958: 399
–
433.
5
Hamilton J B. Ann N Y Acad Sci 1951:
53
: 708
–
728.
6
Norwood O T. South Med J 1975:
68
: 1359
–
1365.
7
Seaton F D. Kansas History: A Journal of the
Central Plains 2004:
27
: 250
–
263.
8
Hamilton J B, Mestler G E. J Gerontol 1969:
24
:
395
–
411.
9
Panchaprateep R, Asawanonda P. Exp Dermatol
2014:
23
: 216
–
218.
10
Nieves A, Garza L A. Exp Dermatol 2014:
23
:
224
–
227.
Figure 2.
Reproduction of the original Hamilton androgenetic alopecia score.
Copyright 1951 Wiley. Used with permission from Hamilton, J. B., patterned loss of
hair in man: types and incidence, Annals of the New York Academy of Sciences,
Wiley.
ª
2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Experimental Dermatology
, 2015,
24
, 412–413
413
Commentary: my favourite historical paper
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