107.A 16-year-old girl presents to the pediatric genetic and endocrine clinic
with short stature, Tanner stage 2 of pubertal development and lack of men-
struation. She is 49 in. tall (normal range for age is 59–68 in. mean 64 in.) and
weighs 65 lb (normal range for age is 92–158 lb, mean is 126 lb.). She has a
short, broad, webbed neck, short fingers and toes, and cubitus valgus.Hor-
monal profile reveals high levels of the gonadotrophins LH and FSH, and very
low levels of estrogen. Ultrasound studies show uterine hypoplasia and
poorly-defined gonadal streaks. Genetic analysis shows a 45, X0 pattern. The
short stature has been linked to reduced protein expression of the short
stature homeobox gene (SHOX). That gene working through specific tran-
scription factors would influence the production of which of the following by
the cells delineated by the box in the accompanying photomicrograph.
Specialized Connective Tissues: Bone and Cartilage 195a. Cyclins
b. Acid phosphatase
c. Alkaline phosphatase
d. Type I collagen
e. Osteocalcin