(1) The alpha subunit comprises 92 amino acids, of which 6 are Lys residues (Morgan, F.G., Birken, S., and Canfield, R.E.
(2) Leu in the common positions (12, 15, 19, and 22) has also been found in human choriogonadotropin pre-alpha subunit [Birken, S., Fetherston, J., Desmond, J., Canfield, R. & Boime, I.