Reproductive endocrinology: functional effects of sex hormone-binding globulin variants.

A new study has found eight single nucleotide polymorphisms in sex hormone-binding globulin that functionally affect its affinity for androgens or estrogens and other biochemical properties. This finding adds to growing concern about the ‘one size fits all’ approach in formulas to calculate free or bioavailable concentrations of estradiol and testosterone. [ABSTRACT FROM AUTHOR]