Binder G, Nakamura A, Schweizer R, et al. - Through retrospectively obtaining data from 7 boys with aromatase excess syndrome (AEXS), researchers sought to examine long-term treatment effects of an aromatase inhibitor. Genetic analysis showed upstream of CYP19A1 a 165,901 bp deletion in 4 German cousins, a 198,662 bp deletion in 2 Japanese brothers and a 387,622 bp tandem duplication in a Japanese boy. Spontaneous growth varied, even within the same family, in AEXS. Data indicate that early-onset, long-term anastrozole inhibition promotes adult height in boys with AEXS.