Comparison of serum FSH and Inhibin B levels between adult male dizygotic and monozygotic twins.
BACKGROUND
FSH hypersecretion occurs in mothers of dizygotic (DZ) twins. Twinning is inherited via both sexes and transmitted through the female. FSH hypersecretion may thus occur in male DZ twins.


METHODS
We assayed FSH and its counter-regulatory hormone, Inhibin B, in 108 adult male DZ and 100 monozygotic (MZ) twins (as controls) and compared our results to published norms.


RESULTS
Inhibin B was elevated and higher in DZ compared with MZ twins with similar FSH.


CONCLUSIONS
The normal FSH: Inhibin B endocrine feedback axis is different in adult male DZ twins. This contributes to the theory that the answer to human DZ twinning lies in the actions of FSH and Inhibin, and in their mutual interaction.
Sutcliffe
Alastair
A
Department of Child Health, Royal Free and University College Medical School, NW3 2PF, London. a.sutcliffe@medsch.ucl.ac.uk
Spoudeas
Helen A
HA
Nair
Devaki
D
Bouloux
Pierre
P
Oliver
Tim
T
Sambrook
Philip
P
Bannister
Wendy
W
Lambalk
Cornelis B
CB
Spector
Tim
T
D000328:Adult; D000368:Aged; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D007265:Inhibins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D014429:Twins, Dizygotic / Q000097:blood*; D014430:Twins, Monozygotic / Q000097:blood*
C422364:inhibin B; D007265:Inhibins; D005640:Follicle Stimulating Hormone