Biochemical solubility of Aβ42 is not altered by an additional copy of the Dp3Tyb, Dp(10)2Yey, or Dp(17)3Yey Hsa21 orthologous regions. Total cortical proteins were biochemically fractionated from 8-month-old mice and Aβ abundance analyzed by MSD assay (6E10). No difference in the abundance of (A) 5 m guanidine hydrochloride-soluble Aβ42 (F(1,12) = 0.128, p = 0.726), (D) 1% Triton X-100-soluble Aβ42 (F(1,12) = 2.863, p = 0.116), or (G) Tris-soluble Aβ42 (F(1,10) = 0.281, p = 0.608) was observed between Dp3Tyb;AppNL-F/NL-F compared with AppNL-F/NL-F controls. AppNL-F/NL-F female n = 2, male n = 6; Dp3Tyb;AppNL-F/NL-F female n = 7, male n = 3. No difference in the abundance of (B) 5 m guanidine hydrochloride-soluble (F(1,11) = 2.337, p = 0.115), (E) 1% Triton X-100-soluble Aβ42 (F(1,11) = 0.145, p = 0.711), or (H) Tris-soluble Aβ42 (F(1,11) = 0.001, p = 0.978) was observed between Dp(10)2Yey;AppNL-F/NL-F compared with AppNL-F/NL-F controls. AppNL-F/NL-F female n = 4, male n = 5; Dp(10)2Yey;AppNL-F/NL-F female n = 6, male n = 3. No difference in the abundance of (C) 5 m guanidine hydrochloride-soluble (F(1,20) = 4.079, p = 0.057), (F) 1% Triton X-100-soluble Aβ42 (F(1,20) = 0.124, p = 0.728), or (I) Tris-soluble (F(1,20) = 0.521, p = 0.479) Aβ42 was observed between Dp(17)3Yey;AppNL-F/NL-F compared with AppNL-F/NL-F controls. AppNL-F/NL-F female n = 7, male n = 5; Dp(17)3Yey;AppNL-F/NL-F female n = 7, male n = 7. Details of negative controls, which do not carry an AppNL-F allele in Table 2. For clarity: Dp3, Dp3Tyb; Dp10, Dp(10)2Yey; Dp17, Dp(17)3Yey. Error bars indicate SEM. Data points represent independent mice.