CYP21A2 and Autoimmune polyendocrinopathy type 1: Fraction of sera positive for antibodies to adrenal cortex (AC-Abs), steroid-producing cells (StC-Abs), cytochrome-P450 21-hydroxylase (CYP21-Abs), cytochrome-P450 cholesterol side-chain cleavage enzyme (CYPscc-Abs), and cytochrome-P450 17α-hydroxylase/17,20 lyase (CYP17-Abs) in cohorts of autoimmune polyglandular syndrome type-1 (APS1) patients, with specification of their ethnic background.