Margolis DJ, Mitra N, Wubbenhorst B, et al. - In this prospective US cohort study involving 741 children [mean [SD] age at onset, 1.97 [2.72] years)] with mild to moderate atopic dermatitis (AD), researchers comprehensively characterized and compared outcomes from targeted sequencing of filaggrin gene (FLG) loss-of-function (LoF) variants in children of African and European ancestry and the relationship of these variants with AD onset and persistence. They evaluated the genetic subcohort of the Pediatric Eczema Elective Registry. In a US cohort of children with mild to moderate AD, the FLG LoF variants vary significantly in race and association with AD persistence. The conventional testing of the four variants that are frequently assessed is insufficient. Any scheduled genetic diagnostic test for AD based on variants of FLG LoF must be inclusive and not based on the variants studied most frequently.