Transcript HGSS Chapter 5: Congenital Adrenal Hyperplasia (CAH)

Congenital Adrenal
Hyperplasia (CAH)
1) Example of genetic heterogeneity.
2) Natural quasi-experiment on the effects
of prenatal androgens on behavior.
Cholesterol
Ambiguous, no
androgens, salt-wasting
desmolase
Pregnenolone
Ambiguous,
androgens,
hypertension
17-a-hydroxylase
low
17-Hydroxypregnenalone
3-b-OHdehydrogenase
Androgens
Virilized,
high
androgens, lethal
17-Hydroxyprogesterone
Virilized,
high
androgens, salt-wasting
21-hydroxylase
11-Deoxycortisol
Virilized,
high
androgens,
hypertension
11-b-hydroxylase
Cortisol
HGSS: Carey: Figure 5.2
Key: Genitalia, androgen level, medical symptom
21-Hydroxylase Deficiency: 21-OHD-CAH
Classic: No or very little enzyme activity (1/15,000 births)
Nonclassic: Low enzyme activity (1/100 births)
Feature:
Classical:
Non-classical:
Prenatal virilization:
Present in Females
Absent
Postnatal virilization:
Males & Females
Variable
Salt-wasting:
> 75% of cases
Absent
Cortisol Deficiency:
100%
Rare
Enzymatic Pathway for Cortisol and Aldosterone
(
: results of 21-ODH-CAH)
Virilized Females:
Adult Virilized emale:
http://psych.unn.ac.uk/users/nick/hormonespp03/sld023.htm
Masculine
Feminine
Toy Preference
CAH
Girls
Control
Boys
CAH
B
o
y
s
Control
Girls
Based on Berenbaum & Hines (1992) for children and Berenbaum (1999) for adolescents
Other Findings:
(1) No difference between CAH boys and control boys on interest
patterns, personality, cognition, and sex orientation.
(2) CAH girls are more masculine in interest patterns than control
girls.
(3) CAH girls have more “masculine” personality traits: more
aggressive, less interested in infants, less maternal, and less
empathetic than control girls.
(4) CAH girls have higher spatial-visualization and spatial
orientation than control girls.
(5) Most CAH girls are heterosexual (c. 70%), but have a higher
rate of same-sex orientation than their sisters.
(6) Biggest difference between CAH and control girls is on
interest patterns.